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3.4 doesn't build #83

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turl opened this issue Oct 5, 2012 · 2 comments
Closed

3.4 doesn't build #83

turl opened this issue Oct 5, 2012 · 2 comments
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@turl
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turl commented Oct 5, 2012

3.4 build fails with the following

drivers/built-in.o: In function rmmod_device_driver': ~/linux-allwinner/drivers/usb/sun4i_usb/manager/usb_msg_center.c:268: undefined reference tosw_usb_device_disable'
drivers/built-in.o: In function insmod_device_driver': ~/linux-allwinner/drivers/usb/sun4i_usb/manager/usb_msg_center.c:240: undefined reference tosw_usb_device_enable'
make: *** [.tmp_vmlinux1] Error 1

@amery
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amery commented Oct 5, 2012

sun4i_crane_defconfig? this is most likely related to #29

@turl
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turl commented Oct 5, 2012

I used allwinner-dev-team@74c0cd3 + 'make oldconfig'

@amery amery closed this as completed Oct 6, 2012
amery pushed a commit that referenced this issue Feb 28, 2013
…device"

This reverts commit eb6b9a8.

Above commit limits GSO capability of gre device to just TSO, but
software GRE-GSO is capable of handling all GSO capabilities.

This patch also fixes following panic which reverted commit introduced:-

BUG: unable to handle kernel NULL pointer dereference at 00000000000000a2
IP: [<ffffffffa0680fd1>] ipgre_tunnel_bind_dev+0x161/0x1f0 [ip_gre]
PGD 42bc19067 PUD 42bca9067 PMD 0
Oops: 0000 [#1] SMP
Pid: 2636, comm: ip Tainted: GF            3.8.0+ #83 Dell Inc. PowerEdge R620/0KCKR5
RIP: 0010:[<ffffffffa0680fd1>]  [<ffffffffa0680fd1>] ipgre_tunnel_bind_dev+0x161/0x1f0 [ip_gre]
RSP: 0018:ffff88042bfcb708  EFLAGS: 00010246
RAX: 00000000000005b6 RBX: ffff88042d2fa000 RCX: 0000000000000044
RDX: 0000000000000018 RSI: 0000000000000078 RDI: 0000000000000060
RBP: ffff88042bfcb748 R08: 0000000000000018 R09: 000000000000000c
R10: 0000000000000020 R11: 000000000101010a R12: ffff88042d2fa800
R13: 0000000000000000 R14: ffff88042d2fa800 R15: ffff88042cd7f650
FS:  00007fa784f55700(0000) GS:ffff88043fd20000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000a2 CR3: 000000042d8b9000 CR4: 00000000000407e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process ip (pid: 2636, threadinfo ffff88042bfca000, task ffff88042d142a80)
Stack:
 0000000100000000 002f000000000000 0a01010100000000 000000000b010101
 ffff88042d2fa800 ffff88042d2fa000 ffff88042bfcb858 ffff88042f418c00
 ffff88042bfcb798 ffffffffa068199a ffff88042bfcb798 ffff88042d2fa830
Call Trace:
 [<ffffffffa068199a>] ipgre_newlink+0xca/0x160 [ip_gre]
 [<ffffffff8143b692>] rtnl_newlink+0x532/0x5f0
 [<ffffffff8143b2fc>] ? rtnl_newlink+0x19c/0x5f0
 [<ffffffff81438978>] rtnetlink_rcv_msg+0x2c8/0x340
 [<ffffffff814386b0>] ? rtnetlink_rcv+0x40/0x40
 [<ffffffff814560f9>] netlink_rcv_skb+0xa9/0xd0
 [<ffffffff81438695>] rtnetlink_rcv+0x25/0x40
 [<ffffffff81455ddc>] netlink_unicast+0x1ac/0x230
 [<ffffffff81456a45>] netlink_sendmsg+0x265/0x380
 [<ffffffff814138c0>] sock_sendmsg+0xb0/0xe0
 [<ffffffff8141141e>] ? move_addr_to_kernel+0x4e/0x90
 [<ffffffff81420445>] ? verify_iovec+0x85/0xf0
 [<ffffffff81414ffd>] __sys_sendmsg+0x3fd/0x420
 [<ffffffff8114b701>] ? handle_mm_fault+0x251/0x3b0
 [<ffffffff8114f39f>] ? vma_link+0xcf/0xe0
 [<ffffffff81415239>] sys_sendmsg+0x49/0x90
 [<ffffffff814ffd19>] system_call_fastpath+0x16/0x1b

CC: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
amery pushed a commit that referenced this issue Nov 12, 2013
Turn it into (for example):

[    0.073380] x86: Booting SMP configuration:
[    0.074005] .... node   #0, CPUs:          #1   #2   #3   #4   #5   #6   #7
[    0.603005] .... node   #1, CPUs:     #8   #9  #10  #11  #12  #13  #14  #15
[    1.200005] .... node   #2, CPUs:    #16  #17  #18  #19  #20  #21  #22  #23
[    1.796005] .... node   #3, CPUs:    #24  #25  #26  #27  #28  #29  #30  #31
[    2.393005] .... node   #4, CPUs:    #32  #33  #34  #35  #36  #37  #38  #39
[    2.996005] .... node   #5, CPUs:    #40  #41  #42  #43  #44  #45  #46  #47
[    3.600005] .... node   #6, CPUs:    #48  #49  #50  #51  #52  #53  #54  #55
[    4.202005] .... node   #7, CPUs:    #56  #57  #58  #59  #60  #61  #62  #63
[    4.811005] .... node   #8, CPUs:    #64  #65  #66  #67  #68  #69  #70  #71
[    5.421006] .... node   #9, CPUs:    #72  #73  #74  #75  #76  #77  #78  #79
[    6.032005] .... node  #10, CPUs:    #80  #81  #82  #83  #84  #85  #86  #87
[    6.648006] .... node  #11, CPUs:    #88  #89  #90  #91  #92  #93  #94  #95
[    7.262005] .... node  #12, CPUs:    #96  #97  #98  #99 #100 #101 #102 #103
[    7.865005] .... node  #13, CPUs:   #104 #105 #106 #107 #108 #109 #110 #111
[    8.466005] .... node  #14, CPUs:   #112 #113 #114 #115 #116 #117 #118 #119
[    9.073006] .... node  #15, CPUs:   #120 #121 #122 #123 #124 #125 #126 #127
[    9.679901] x86: Booted up 16 nodes, 128 CPUs

and drop useless elements.

Change num_digits() to hpa's division-avoiding, cell-phone-typed
version which he went at great lengths and pains to submit on a
Saturday evening.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: huawei.libin@huawei.com
Cc: wangyijing@huawei.com
Cc: fenghua.yu@intel.com
Cc: guohanjun@huawei.com
Cc: paul.gortmaker@windriver.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130930095624.GB16383@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
amery pushed a commit that referenced this issue Feb 17, 2016
kasan reported the following error when i ran xfstest:

[  701.826854] ==================================================================
[  701.826864] BUG: KASAN: use-after-free in dio_bio_complete+0x41a/0x600 at addr ffff880080b95f94
[  701.826870] Read of size 4 by task loop2/3874
[  701.826879] page:ffffea000202e540 count:0 mapcount:0 mapping:          (null) index:0x0
[  701.826890] flags: 0x100000000000000()
[  701.826895] page dumped because: kasan: bad access detected
[  701.826904] CPU: 3 PID: 3874 Comm: loop2 Tainted: G    B   W    L  4.5.0-rc1-next-20160129 #83
[  701.826910] Hardware name: LENOVO 23205NG/23205NG, BIOS G2ET95WW (2.55 ) 07/09/2013
[  701.826917]  ffff88008fadf800 ffff88008fadf758 ffffffff81ca67bb 0000000041b58ab3
[  701.826941]  ffffffff830d1e74 ffffffff81ca6724 ffff88008fadf748 ffffffff8161c05c
[  701.826963]  0000000000000282 ffff88008fadf800 ffffed0010172bf2 ffffea000202e540
[  701.826987] Call Trace:
[  701.826997]  [<ffffffff81ca67bb>] dump_stack+0x97/0xdc
[  701.827005]  [<ffffffff81ca6724>] ? _atomic_dec_and_lock+0xc4/0xc4
[  701.827014]  [<ffffffff8161c05c>] ? __dump_page+0x32c/0x490
[  701.827023]  [<ffffffff816b0d03>] kasan_report_error+0x5f3/0x8b0
[  701.827033]  [<ffffffff817c302a>] ? dio_bio_complete+0x41a/0x600
[  701.827040]  [<ffffffff816b1119>] __asan_report_load4_noabort+0x59/0x80
[  701.827048]  [<ffffffff817c302a>] ? dio_bio_complete+0x41a/0x600
[  701.827053]  [<ffffffff817c302a>] dio_bio_complete+0x41a/0x600
[  701.827057]  [<ffffffff81bd19c8>] ? blk_queue_exit+0x108/0x270
[  701.827060]  [<ffffffff817c32b0>] dio_bio_end_aio+0xa0/0x4d0
[  701.827063]  [<ffffffff817c3210>] ? dio_bio_complete+0x600/0x600
[  701.827067]  [<ffffffff81bd2806>] ? blk_account_io_completion+0x316/0x5d0
[  701.827070]  [<ffffffff81bafe89>] bio_endio+0x79/0x200
[  701.827074]  [<ffffffff81bd2c9f>] blk_update_request+0x1df/0xc50
[  701.827078]  [<ffffffff81c02c27>] blk_mq_end_request+0x57/0x120
[  701.827081]  [<ffffffff81c03670>] __blk_mq_complete_request+0x310/0x590
[  701.827084]  [<ffffffff812348d8>] ? set_next_entity+0x2f8/0x2ed0
[  701.827088]  [<ffffffff8124b34d>] ? put_prev_entity+0x22d/0x2a70
[  701.827091]  [<ffffffff81c0394b>] blk_mq_complete_request+0x5b/0x80
[  701.827094]  [<ffffffff821e2a33>] loop_queue_work+0x273/0x19d0
[  701.827098]  [<ffffffff811f6578>] ? finish_task_switch+0x1c8/0x8e0
[  701.827101]  [<ffffffff8129d058>] ? trace_hardirqs_on_caller+0x18/0x6c0
[  701.827104]  [<ffffffff821e27c0>] ? lo_read_simple+0x890/0x890
[  701.827108]  [<ffffffff8129dd60>] ? debug_check_no_locks_freed+0x350/0x350
[  701.827111]  [<ffffffff811f63b0>] ? __hrtick_start+0x130/0x130
[  701.827115]  [<ffffffff82a0c8f6>] ? __schedule+0x936/0x20b0
[  701.827118]  [<ffffffff811dd6bd>] ? kthread_worker_fn+0x3ed/0x8d0
[  701.827121]  [<ffffffff811dd4ed>] ? kthread_worker_fn+0x21d/0x8d0
[  701.827125]  [<ffffffff8129d058>] ? trace_hardirqs_on_caller+0x18/0x6c0
[  701.827128]  [<ffffffff811dd57f>] kthread_worker_fn+0x2af/0x8d0
[  701.827132]  [<ffffffff811dd2d0>] ? __init_kthread_worker+0x170/0x170
[  701.827135]  [<ffffffff82a1ea46>] ? _raw_spin_unlock_irqrestore+0x36/0x60
[  701.827138]  [<ffffffff811dd2d0>] ? __init_kthread_worker+0x170/0x170
[  701.827141]  [<ffffffff811dd2d0>] ? __init_kthread_worker+0x170/0x170
[  701.827144]  [<ffffffff811dd00b>] kthread+0x24b/0x3a0
[  701.827148]  [<ffffffff811dcdc0>] ? kthread_create_on_node+0x4c0/0x4c0
[  701.827151]  [<ffffffff8129d70d>] ? trace_hardirqs_on+0xd/0x10
[  701.827155]  [<ffffffff8116d41d>] ? do_group_exit+0xdd/0x350
[  701.827158]  [<ffffffff811dcdc0>] ? kthread_create_on_node+0x4c0/0x4c0
[  701.827161]  [<ffffffff82a1f52f>] ret_from_fork+0x3f/0x70
[  701.827165]  [<ffffffff811dcdc0>] ? kthread_create_on_node+0x4c0/0x4c0
[  701.827167] Memory state around the buggy address:
[  701.827170]  ffff880080b95e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  701.827172]  ffff880080b95f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  701.827175] >ffff880080b95f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  701.827177]                          ^
[  701.827179]  ffff880080b96000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  701.827182]  ffff880080b96080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[  701.827183] ==================================================================

The problem is that bio_check_pages_dirty calls bio_put, so we must
not access bio fields after bio_check_pages_dirty.

Fixes: 9b81c84 ("block: don't access bio->bi_error after bio_put()").
Signed-off-by: Mike Krinkin <krinkin.m.u@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
amery pushed a commit that referenced this issue Dec 15, 2016
There is at least one Chelsio 10Gb card which uses VPD area to store some
non-standard blocks (example below).  However pci_vpd_size() returns the
length of the first block only assuming that there can be only one VPD "End
Tag".

Since 4e1a635 ("vfio/pci: Use kernel VPD access functions"), VFIO
blocks access beyond that offset, which prevents the guest "cxgb3" driver
from probing the device.  The host system does not have this problem as its
driver accesses the config space directly without pci_read_vpd().

Add a quirk to override the VPD size to a bigger value.  The maximum size
is taken from EEPROMSIZE in drivers/net/ethernet/chelsio/cxgb3/common.h.
We do not read the tag as the cxgb3 driver does as the driver supports
writing to EEPROM/VPD and when it writes, it only checks for 8192 bytes
boundary.  The quirk is registered for all devices supported by the cxgb3
driver.

This adds a quirk to the PCI layer (not to the cxgb3 driver) as the cxgb3
driver itself accesses VPD directly and the problem only exists with the
vfio-pci driver (when cxgb3 is not running on the host and may not be even
loaded) which blocks accesses beyond the first block of VPD data.  However
vfio-pci itself does not have quirks mechanism so we add it to PCI.

This is the controller:
Ethernet controller [0200]: Chelsio Communications Inc T310 10GbE Single Port Adapter [1425:0030]

This is what I parsed from its VPD:
===
b'\x82*\x0010 Gigabit Ethernet-SR PCI Express Adapter\x90J\x00EC\x07D76809 FN\x0746K'
 0000 Large item 42 bytes; name 0x2 Identifier String
	b'10 Gigabit Ethernet-SR PCI Express Adapter'
 002d Large item 74 bytes; name 0x10
	#00 [EC] len=7: b'D76809 '
	#0a [FN] len=7: b'46K7897'
	#14 [PN] len=7: b'46K7897'
	#1e [MN] len=4: b'1037'
	#25 [FC] len=4: b'5769'
	#2c [SN] len=12: b'YL102035603V'
	#3b [NA] len=12: b'00145E992ED1'
 007a Small item 1 bytes; name 0xf End Tag

 0c00 Large item 16 bytes; name 0x2 Identifier String
	b'S310E-SR-X      '
 0c13 Large item 234 bytes; name 0x10
	#00 [PN] len=16: b'TBD             '
	#13 [EC] len=16: b'110107730D2     '
	#26 [SN] len=16: b'97YL102035603V  '
	#39 [NA] len=12: b'00145E992ED1'
	#48 [V0] len=6: b'175000'
	#51 [V1] len=6: b'266666'
	#5a [V2] len=6: b'266666'
	#63 [V3] len=6: b'2000  '
	#6c [V4] len=2: b'1 '
	#71 [V5] len=6: b'c2    '
	#7a [V6] len=6: b'0     '
	#83 [V7] len=2: b'1 '
	#88 [V8] len=2: b'0 '
	#8d [V9] len=2: b'0 '
	#92 [VA] len=2: b'0 '
	#97 [RV] len=80: b's\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'...
 0d00 Large item 252 bytes; name 0x11
	#00 [VC] len=16: b'122310_1222 dp  '
	#13 [VD] len=16: b'610-0001-00 H1\x00\x00'
	#26 [VE] len=16: b'122310_1353 fp  '
	#39 [VF] len=16: b'610-0001-00 H1\x00\x00'
	#4c [RW] len=173: b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'...
 0dff Small item 0 bytes; name 0xf End Tag

10f3 Large item 13315 bytes; name 0x62
!!! unknown item name 98: b'\xd0\x03\x00@`\x0c\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00'
===

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Jan 13, 2017
commit 1c7de2b upstream.

There is at least one Chelsio 10Gb card which uses VPD area to store some
non-standard blocks (example below).  However pci_vpd_size() returns the
length of the first block only assuming that there can be only one VPD "End
Tag".

Since 4e1a635 ("vfio/pci: Use kernel VPD access functions"), VFIO
blocks access beyond that offset, which prevents the guest "cxgb3" driver
from probing the device.  The host system does not have this problem as its
driver accesses the config space directly without pci_read_vpd().

Add a quirk to override the VPD size to a bigger value.  The maximum size
is taken from EEPROMSIZE in drivers/net/ethernet/chelsio/cxgb3/common.h.
We do not read the tag as the cxgb3 driver does as the driver supports
writing to EEPROM/VPD and when it writes, it only checks for 8192 bytes
boundary.  The quirk is registered for all devices supported by the cxgb3
driver.

This adds a quirk to the PCI layer (not to the cxgb3 driver) as the cxgb3
driver itself accesses VPD directly and the problem only exists with the
vfio-pci driver (when cxgb3 is not running on the host and may not be even
loaded) which blocks accesses beyond the first block of VPD data.  However
vfio-pci itself does not have quirks mechanism so we add it to PCI.

This is the controller:
Ethernet controller [0200]: Chelsio Communications Inc T310 10GbE Single Port Adapter [1425:0030]

This is what I parsed from its VPD:
===
b'\x82*\x0010 Gigabit Ethernet-SR PCI Express Adapter\x90J\x00EC\x07D76809 FN\x0746K'
 0000 Large item 42 bytes; name 0x2 Identifier String
	b'10 Gigabit Ethernet-SR PCI Express Adapter'
 002d Large item 74 bytes; name 0x10
	#00 [EC] len=7: b'D76809 '
	#0a [FN] len=7: b'46K7897'
	linux-sunxi#14 [PN] len=7: b'46K7897'
	#1e [MN] len=4: b'1037'
	linux-sunxi#25 [FC] len=4: b'5769'
	#2c [SN] len=12: b'YL102035603V'
	#3b [NA] len=12: b'00145E992ED1'
 007a Small item 1 bytes; name 0xf End Tag

 0c00 Large item 16 bytes; name 0x2 Identifier String
	b'S310E-SR-X      '
 0c13 Large item 234 bytes; name 0x10
	#00 [PN] len=16: b'TBD             '
	linux-sunxi#13 [EC] len=16: b'110107730D2     '
	linux-sunxi#26 [SN] len=16: b'97YL102035603V  '
	linux-sunxi#39 [NA] len=12: b'00145E992ED1'
	linux-sunxi#48 [V0] len=6: b'175000'
	linux-sunxi#51 [V1] len=6: b'266666'
	#5a [V2] len=6: b'266666'
	linux-sunxi#63 [V3] len=6: b'2000  '
	#6c [V4] len=2: b'1 '
	linux-sunxi#71 [V5] len=6: b'c2    '
	#7a [V6] len=6: b'0     '
	linux-sunxi#83 [V7] len=2: b'1 '
	linux-sunxi#88 [V8] len=2: b'0 '
	#8d [V9] len=2: b'0 '
	linux-sunxi#92 [VA] len=2: b'0 '
	linux-sunxi#97 [RV] len=80: b's\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'...
 0d00 Large item 252 bytes; name 0x11
	#00 [VC] len=16: b'122310_1222 dp  '
	linux-sunxi#13 [VD] len=16: b'610-0001-00 H1\x00\x00'
	linux-sunxi#26 [VE] len=16: b'122310_1353 fp  '
	linux-sunxi#39 [VF] len=16: b'610-0001-00 H1\x00\x00'
	#4c [RW] len=173: b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'...
 0dff Small item 0 bytes; name 0xf End Tag

10f3 Large item 13315 bytes; name 0x62
!!! unknown item name 98: b'\xd0\x03\x00@`\x0c\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00'
===

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue May 4, 2017
Patch series "kasan: improve error reports", v2.

This patchset improves KASAN reports by making them easier to read and a
little more detailed.  Also improves mm/kasan/report.c readability.

Effectively changes a use-after-free report to:

  ==================================================================
  BUG: KASAN: use-after-free in kmalloc_uaf+0xaa/0xb6 [test_kasan]
  Write of size 1 at addr ffff88006aa59da8 by task insmod/3951

  CPU: 1 PID: 3951 Comm: insmod Tainted: G    B           4.10.0+ #84
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Call Trace:
   dump_stack+0x292/0x398
   print_address_description+0x73/0x280
   kasan_report.part.2+0x207/0x2f0
   __asan_report_store1_noabort+0x2c/0x30
   kmalloc_uaf+0xaa/0xb6 [test_kasan]
   kmalloc_tests_init+0x4f/0xa48 [test_kasan]
   do_one_initcall+0xf3/0x390
   do_init_module+0x215/0x5d0
   load_module+0x54de/0x82b0
   SYSC_init_module+0x3be/0x430
   SyS_init_module+0x9/0x10
   entry_SYSCALL_64_fastpath+0x1f/0xc2
  RIP: 0033:0x7f22cfd0b9da
  RSP: 002b:00007ffe69118a78 EFLAGS: 00000206 ORIG_RAX: 00000000000000af
  RAX: ffffffffffffffda RBX: 0000555671242090 RCX: 00007f22cfd0b9da
  RDX: 00007f22cffcaf88 RSI: 000000000004df7e RDI: 00007f22d0399000
  RBP: 00007f22cffcaf88 R08: 0000000000000003 R09: 0000000000000000
  R10: 00007f22cfd07d0a R11: 0000000000000206 R12: 0000555671243190
  R13: 000000000001fe81 R14: 0000000000000000 R15: 0000000000000004

  Allocated by task 3951:
   save_stack_trace+0x16/0x20
   save_stack+0x43/0xd0
   kasan_kmalloc+0xad/0xe0
   kmem_cache_alloc_trace+0x82/0x270
   kmalloc_uaf+0x56/0xb6 [test_kasan]
   kmalloc_tests_init+0x4f/0xa48 [test_kasan]
   do_one_initcall+0xf3/0x390
   do_init_module+0x215/0x5d0
   load_module+0x54de/0x82b0
   SYSC_init_module+0x3be/0x430
   SyS_init_module+0x9/0x10
   entry_SYSCALL_64_fastpath+0x1f/0xc2

  Freed by task 3951:
   save_stack_trace+0x16/0x20
   save_stack+0x43/0xd0
   kasan_slab_free+0x72/0xc0
   kfree+0xe8/0x2b0
   kmalloc_uaf+0x85/0xb6 [test_kasan]
   kmalloc_tests_init+0x4f/0xa48 [test_kasan]
   do_one_initcall+0xf3/0x390
   do_init_module+0x215/0x5d0
   load_module+0x54de/0x82b0
   SYSC_init_module+0x3be/0x430
   SyS_init_module+0x9/0x10
   entry_SYSCALL_64_fastpath+0x1f/0xc

  The buggy address belongs to the object at ffff88006aa59da0
   which belongs to the cache kmalloc-16 of size 16
  The buggy address is located 8 bytes inside of
   16-byte region [ffff88006aa59da0, ffff88006aa59db0)
  The buggy address belongs to the page:
  page:ffffea0001aa9640 count:1 mapcount:0 mapping:          (null) index:0x0
  flags: 0x100000000000100(slab)
  raw: 0100000000000100 0000000000000000 0000000000000000 0000000180800080
  raw: ffffea0001abe380 0000000700000007 ffff88006c401b40 0000000000000000
  page dumped because: kasan: bad access detected

  Memory state around the buggy address:
   ffff88006aa59c80: 00 00 fc fc 00 00 fc fc 00 00 fc fc 00 00 fc fc
   ffff88006aa59d00: 00 00 fc fc 00 00 fc fc 00 00 fc fc 00 00 fc fc
  >ffff88006aa59d80: fb fb fc fc fb fb fc fc fb fb fc fc fb fb fc fc
                                    ^
   ffff88006aa59e00: fb fb fc fc fb fb fc fc fb fb fc fc fb fb fc fc
   ffff88006aa59e80: fb fb fc fc 00 00 fc fc 00 00 fc fc 00 00 fc fc
  ==================================================================

from:

  ==================================================================
  BUG: KASAN: use-after-free in kmalloc_uaf+0xaa/0xb6 [test_kasan] at addr ffff88006c4dcb28
  Write of size 1 by task insmod/3984
  CPU: 1 PID: 3984 Comm: insmod Tainted: G    B           4.10.0+ #83
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Call Trace:
   dump_stack+0x292/0x398
   kasan_object_err+0x1c/0x70
   kasan_report.part.1+0x20e/0x4e0
   __asan_report_store1_noabort+0x2c/0x30
   kmalloc_uaf+0xaa/0xb6 [test_kasan]
   kmalloc_tests_init+0x4f/0xa48 [test_kasan]
   do_one_initcall+0xf3/0x390
   do_init_module+0x215/0x5d0
   load_module+0x54de/0x82b0
   SYSC_init_module+0x3be/0x430
   SyS_init_module+0x9/0x10
   entry_SYSCALL_64_fastpath+0x1f/0xc2
  RIP: 0033:0x7feca0f779da
  RSP: 002b:00007ffdfeae5218 EFLAGS: 00000206 ORIG_RAX: 00000000000000af
  RAX: ffffffffffffffda RBX: 000055a064c13090 RCX: 00007feca0f779da
  RDX: 00007feca1236f88 RSI: 000000000004df7e RDI: 00007feca1605000
  RBP: 00007feca1236f88 R08: 0000000000000003 R09: 0000000000000000
  R10: 00007feca0f73d0a R11: 0000000000000206 R12: 000055a064c14190
  R13: 000000000001fe81 R14: 0000000000000000 R15: 0000000000000004
  Object at ffff88006c4dcb20, in cache kmalloc-16 size: 16
  Allocated:
  PID = 3984
   save_stack_trace+0x16/0x20
   save_stack+0x43/0xd0
   kasan_kmalloc+0xad/0xe0
   kmem_cache_alloc_trace+0x82/0x270
   kmalloc_uaf+0x56/0xb6 [test_kasan]
   kmalloc_tests_init+0x4f/0xa48 [test_kasan]
   do_one_initcall+0xf3/0x390
   do_init_module+0x215/0x5d0
   load_module+0x54de/0x82b0
   SYSC_init_module+0x3be/0x430
   SyS_init_module+0x9/0x10
   entry_SYSCALL_64_fastpath+0x1f/0xc2
  Freed:
  PID = 3984
   save_stack_trace+0x16/0x20
   save_stack+0x43/0xd0
   kasan_slab_free+0x73/0xc0
   kfree+0xe8/0x2b0
   kmalloc_uaf+0x85/0xb6 [test_kasan]
   kmalloc_tests_init+0x4f/0xa48 [test_kasan]
   do_one_initcall+0xf3/0x390
   do_init_module+0x215/0x5d0
   load_module+0x54de/0x82b0
   SYSC_init_module+0x3be/0x430
   SyS_init_module+0x9/0x10
   entry_SYSCALL_64_fastpath+0x1f/0xc2
  Memory state around the buggy address:
   ffff88006c4dca00: fb fb fc fc fb fb fc fc fb fb fc fc fb fb fc fc
   ffff88006c4dca80: fb fb fc fc fb fb fc fc fb fb fc fc fb fb fc fc
  >ffff88006c4dcb00: fb fb fc fc fb fb fc fc fb fb fc fc fb fb fc fc
                                    ^
   ffff88006c4dcb80: fb fb fc fc 00 00 fc fc fb fb fc fc fb fb fc fc
   ffff88006c4dcc00: fb fb fc fc fb fb fc fc fb fb fc fc fb fb fc fc
  ==================================================================

This patch (of 9):

Introduce get_shadow_bug_type() function, which determines bug type
based on the shadow value for a particular kernel address.  Introduce
get_wild_bug_type() function, which determines bug type for addresses
which don't have a corresponding shadow value.

Link: http://lkml.kernel.org/r/20170302134851.101218-2-andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
amery pushed a commit that referenced this issue Apr 20, 2018
syzbot/KMSAN reported an uninit-value in tcp_parse_options() [1]

I believe this was caused by a TCP_MD5SIG being set on live
flow.

This is highly unexpected, since TCP option space is limited.

For instance, presence of TCP MD5 option automatically disables
TCP TimeStamp option at SYN/SYNACK time, which we can not do
once flow has been established.

Really, adding/deleting an MD5 key only makes sense on sockets
in CLOSE or LISTEN state.

[1]
BUG: KMSAN: uninit-value in tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720
CPU: 1 PID: 6177 Comm: syzkaller192004 Not tainted 4.16.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720
 tcp_fast_parse_options net/ipv4/tcp_input.c:3858 [inline]
 tcp_validate_incoming+0x4f1/0x2790 net/ipv4/tcp_input.c:5184
 tcp_rcv_established+0xf60/0x2bb0 net/ipv4/tcp_input.c:5453
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 release_sock+0x97/0x2a0 net/core/sock.c:2786
 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x448fe9
RSP: 002b:00007fd472c64d38 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000006e5a30 RCX: 0000000000448fe9
RDX: 000000000000029f RSI: 0000000020a88f88 RDI: 0000000000000004
RBP: 00000000006e5a34 R08: 0000000020e68000 R09: 0000000000000010
R10: 00000000200007fd R11: 0000000000000216 R12: 0000000000000000
R13: 00007fff074899ef R14: 00007fd472c659c0 R15: 0000000000000009

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:984 [inline]
 tcp_send_ack+0x18c/0x910 net/ipv4/tcp_output.c:3624
 __tcp_ack_snd_check net/ipv4/tcp_input.c:5040 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5053 [inline]
 tcp_rcv_established+0x2103/0x2bb0 net/ipv4/tcp_input.c:5469
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 release_sock+0x97/0x2a0 net/core/sock.c:2786
 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: cfb6eeb ("[TCP]: MD5 Signature Option (RFC2385) support.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
amery pushed a commit that referenced this issue Apr 20, 2018
Since neigh_dump_table() calls nlmsg_parse() without giving policy
constraints, attributes can have arbirary size that we must validate

Reported by syzbot/KMSAN :

BUG: KMSAN: uninit-value in neigh_master_filtered net/core/neighbour.c:2292 [inline]
BUG: KMSAN: uninit-value in neigh_dump_table net/core/neighbour.c:2348 [inline]
BUG: KMSAN: uninit-value in neigh_dump_info+0x1af0/0x2250 net/core/neighbour.c:2438
CPU: 1 PID: 3575 Comm: syzkaller268891 Not tainted 4.16.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 neigh_master_filtered net/core/neighbour.c:2292 [inline]
 neigh_dump_table net/core/neighbour.c:2348 [inline]
 neigh_dump_info+0x1af0/0x2250 net/core/neighbour.c:2438
 netlink_dump+0x9ad/0x1540 net/netlink/af_netlink.c:2225
 __netlink_dump_start+0x1167/0x12a0 net/netlink/af_netlink.c:2322
 netlink_dump_start include/linux/netlink.h:214 [inline]
 rtnetlink_rcv_msg+0x1435/0x1560 net/core/rtnetlink.c:4598
 netlink_rcv_skb+0x355/0x5f0 net/netlink/af_netlink.c:2447
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4653
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0x1672/0x1750 net/netlink/af_netlink.c:1337
 netlink_sendmsg+0x1048/0x1310 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046
 __sys_sendmsg net/socket.c:2080 [inline]
 SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091
 SyS_sendmsg+0x54/0x80 net/socket.c:2087
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x43fed9
RSP: 002b:00007ffddbee2798 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fed9
RDX: 0000000000000000 RSI: 0000000020005000 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000213 R12: 0000000000401800
R13: 0000000000401890 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:984 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1183 [inline]
 netlink_sendmsg+0x9a6/0x1310 net/netlink/af_netlink.c:1875
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046
 __sys_sendmsg net/socket.c:2080 [inline]
 SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091
 SyS_sendmsg+0x54/0x80 net/socket.c:2087
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: 21fdd09 ("net: Add support for filtering neigh dump by master device")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsa@cumulusnetworks.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
amery pushed a commit that referenced this issue Apr 20, 2018
In order to remove the race caught by syzbot [1], we need
to lock the socket before using po->tp_version as this could
change under us otherwise.

This means lock_sock() and release_sock() must be done by
packet_set_ring() callers.

[1] :
BUG: KMSAN: uninit-value in packet_set_ring+0x1254/0x3870 net/packet/af_packet.c:4249
CPU: 0 PID: 20195 Comm: syzkaller707632 Not tainted 4.16.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 packet_set_ring+0x1254/0x3870 net/packet/af_packet.c:4249
 packet_setsockopt+0x12c6/0x5a90 net/packet/af_packet.c:3662
 SYSC_setsockopt+0x4b8/0x570 net/socket.c:1849
 SyS_setsockopt+0x76/0xa0 net/socket.c:1828
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x449099
RSP: 002b:00007f42b5307ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 000000000070003c RCX: 0000000000449099
RDX: 0000000000000005 RSI: 0000000000000107 RDI: 0000000000000003
RBP: 0000000000700038 R08: 000000000000001c R09: 0000000000000000
R10: 00000000200000c0 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000080eecf R14: 00007f42b53089c0 R15: 0000000000000001

Local variable description: ----req_u@packet_setsockopt
Variable was created at:
 packet_setsockopt+0x13f/0x5a90 net/packet/af_packet.c:3612
 SYSC_setsockopt+0x4b8/0x570 net/socket.c:1849

Fixes: f6fb8f1 ("af-packet: TPACKET_V3 flexible buffer implementation.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Apr 29, 2018
[ Upstream commit 5171b37 ]

In order to remove the race caught by syzbot [1], we need
to lock the socket before using po->tp_version as this could
change under us otherwise.

This means lock_sock() and release_sock() must be done by
packet_set_ring() callers.

[1] :
BUG: KMSAN: uninit-value in packet_set_ring+0x1254/0x3870 net/packet/af_packet.c:4249
CPU: 0 PID: 20195 Comm: syzkaller707632 Not tainted 4.16.0+ linux-sunxi#83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 packet_set_ring+0x1254/0x3870 net/packet/af_packet.c:4249
 packet_setsockopt+0x12c6/0x5a90 net/packet/af_packet.c:3662
 SYSC_setsockopt+0x4b8/0x570 net/socket.c:1849
 SyS_setsockopt+0x76/0xa0 net/socket.c:1828
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x449099
RSP: 002b:00007f42b5307ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 000000000070003c RCX: 0000000000449099
RDX: 0000000000000005 RSI: 0000000000000107 RDI: 0000000000000003
RBP: 0000000000700038 R08: 000000000000001c R09: 0000000000000000
R10: 00000000200000c0 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000080eecf R14: 00007f42b53089c0 R15: 0000000000000001

Local variable description: ----req_u@packet_setsockopt
Variable was created at:
 packet_setsockopt+0x13f/0x5a90 net/packet/af_packet.c:3612
 SYSC_setsockopt+0x4b8/0x570 net/socket.c:1849

Fixes: f6fb8f1 ("af-packet: TPACKET_V3 flexible buffer implementation.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Apr 29, 2018
[ Upstream commit 7212303 ]

syzbot/KMSAN reported an uninit-value in tcp_parse_options() [1]

I believe this was caused by a TCP_MD5SIG being set on live
flow.

This is highly unexpected, since TCP option space is limited.

For instance, presence of TCP MD5 option automatically disables
TCP TimeStamp option at SYN/SYNACK time, which we can not do
once flow has been established.

Really, adding/deleting an MD5 key only makes sense on sockets
in CLOSE or LISTEN state.

[1]
BUG: KMSAN: uninit-value in tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720
CPU: 1 PID: 6177 Comm: syzkaller192004 Not tainted 4.16.0+ linux-sunxi#83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720
 tcp_fast_parse_options net/ipv4/tcp_input.c:3858 [inline]
 tcp_validate_incoming+0x4f1/0x2790 net/ipv4/tcp_input.c:5184
 tcp_rcv_established+0xf60/0x2bb0 net/ipv4/tcp_input.c:5453
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 release_sock+0x97/0x2a0 net/core/sock.c:2786
 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x448fe9
RSP: 002b:00007fd472c64d38 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000006e5a30 RCX: 0000000000448fe9
RDX: 000000000000029f RSI: 0000000020a88f88 RDI: 0000000000000004
RBP: 00000000006e5a34 R08: 0000000020e68000 R09: 0000000000000010
R10: 00000000200007fd R11: 0000000000000216 R12: 0000000000000000
R13: 00007fff074899ef R14: 00007fd472c659c0 R15: 0000000000000009

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:984 [inline]
 tcp_send_ack+0x18c/0x910 net/ipv4/tcp_output.c:3624
 __tcp_ack_snd_check net/ipv4/tcp_input.c:5040 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5053 [inline]
 tcp_rcv_established+0x2103/0x2bb0 net/ipv4/tcp_input.c:5469
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 release_sock+0x97/0x2a0 net/core/sock.c:2786
 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: cfb6eeb ("[TCP]: MD5 Signature Option (RFC2385) support.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Apr 29, 2018
[ Upstream commit 7dd07c1 ]

Since neigh_dump_table() calls nlmsg_parse() without giving policy
constraints, attributes can have arbirary size that we must validate

Reported by syzbot/KMSAN :

BUG: KMSAN: uninit-value in neigh_master_filtered net/core/neighbour.c:2292 [inline]
BUG: KMSAN: uninit-value in neigh_dump_table net/core/neighbour.c:2348 [inline]
BUG: KMSAN: uninit-value in neigh_dump_info+0x1af0/0x2250 net/core/neighbour.c:2438
CPU: 1 PID: 3575 Comm: syzkaller268891 Not tainted 4.16.0+ linux-sunxi#83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 neigh_master_filtered net/core/neighbour.c:2292 [inline]
 neigh_dump_table net/core/neighbour.c:2348 [inline]
 neigh_dump_info+0x1af0/0x2250 net/core/neighbour.c:2438
 netlink_dump+0x9ad/0x1540 net/netlink/af_netlink.c:2225
 __netlink_dump_start+0x1167/0x12a0 net/netlink/af_netlink.c:2322
 netlink_dump_start include/linux/netlink.h:214 [inline]
 rtnetlink_rcv_msg+0x1435/0x1560 net/core/rtnetlink.c:4598
 netlink_rcv_skb+0x355/0x5f0 net/netlink/af_netlink.c:2447
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4653
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0x1672/0x1750 net/netlink/af_netlink.c:1337
 netlink_sendmsg+0x1048/0x1310 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046
 __sys_sendmsg net/socket.c:2080 [inline]
 SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091
 SyS_sendmsg+0x54/0x80 net/socket.c:2087
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x43fed9
RSP: 002b:00007ffddbee2798 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fed9
RDX: 0000000000000000 RSI: 0000000020005000 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000213 R12: 0000000000401800
R13: 0000000000401890 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:984 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1183 [inline]
 netlink_sendmsg+0x9a6/0x1310 net/netlink/af_netlink.c:1875
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046
 __sys_sendmsg net/socket.c:2080 [inline]
 SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091
 SyS_sendmsg+0x54/0x80 net/socket.c:2087
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: 21fdd09 ("net: Add support for filtering neigh dump by master device")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsa@cumulusnetworks.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Apr 30, 2018
[ Upstream commit 7212303 ]

syzbot/KMSAN reported an uninit-value in tcp_parse_options() [1]

I believe this was caused by a TCP_MD5SIG being set on live
flow.

This is highly unexpected, since TCP option space is limited.

For instance, presence of TCP MD5 option automatically disables
TCP TimeStamp option at SYN/SYNACK time, which we can not do
once flow has been established.

Really, adding/deleting an MD5 key only makes sense on sockets
in CLOSE or LISTEN state.

[1]
BUG: KMSAN: uninit-value in tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720
CPU: 1 PID: 6177 Comm: syzkaller192004 Not tainted 4.16.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 tcp_parse_options+0xd74/0x1a30 net/ipv4/tcp_input.c:3720
 tcp_fast_parse_options net/ipv4/tcp_input.c:3858 [inline]
 tcp_validate_incoming+0x4f1/0x2790 net/ipv4/tcp_input.c:5184
 tcp_rcv_established+0xf60/0x2bb0 net/ipv4/tcp_input.c:5453
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 release_sock+0x97/0x2a0 net/core/sock.c:2786
 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x448fe9
RSP: 002b:00007fd472c64d38 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000006e5a30 RCX: 0000000000448fe9
RDX: 000000000000029f RSI: 0000000020a88f88 RDI: 0000000000000004
RBP: 00000000006e5a34 R08: 0000000020e68000 R09: 0000000000000010
R10: 00000000200007fd R11: 0000000000000216 R12: 0000000000000000
R13: 00007fff074899ef R14: 00007fd472c659c0 R15: 0000000000000009

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:984 [inline]
 tcp_send_ack+0x18c/0x910 net/ipv4/tcp_output.c:3624
 __tcp_ack_snd_check net/ipv4/tcp_input.c:5040 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5053 [inline]
 tcp_rcv_established+0x2103/0x2bb0 net/ipv4/tcp_input.c:5469
 tcp_v4_do_rcv+0x6cd/0xd90 net/ipv4/tcp_ipv4.c:1469
 sk_backlog_rcv include/net/sock.h:908 [inline]
 __release_sock+0x2d6/0x680 net/core/sock.c:2271
 release_sock+0x97/0x2a0 net/core/sock.c:2786
 tcp_sendmsg+0xd6/0x100 net/ipv4/tcp.c:1464
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: cfb6eeb ("[TCP]: MD5 Signature Option (RFC2385) support.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Apr 30, 2018
[ Upstream commit 5171b37 ]

In order to remove the race caught by syzbot [1], we need
to lock the socket before using po->tp_version as this could
change under us otherwise.

This means lock_sock() and release_sock() must be done by
packet_set_ring() callers.

[1] :
BUG: KMSAN: uninit-value in packet_set_ring+0x1254/0x3870 net/packet/af_packet.c:4249
CPU: 0 PID: 20195 Comm: syzkaller707632 Not tainted 4.16.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 packet_set_ring+0x1254/0x3870 net/packet/af_packet.c:4249
 packet_setsockopt+0x12c6/0x5a90 net/packet/af_packet.c:3662
 SYSC_setsockopt+0x4b8/0x570 net/socket.c:1849
 SyS_setsockopt+0x76/0xa0 net/socket.c:1828
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x449099
RSP: 002b:00007f42b5307ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 000000000070003c RCX: 0000000000449099
RDX: 0000000000000005 RSI: 0000000000000107 RDI: 0000000000000003
RBP: 0000000000700038 R08: 000000000000001c R09: 0000000000000000
R10: 00000000200000c0 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000080eecf R14: 00007f42b53089c0 R15: 0000000000000001

Local variable description: ----req_u@packet_setsockopt
Variable was created at:
 packet_setsockopt+0x13f/0x5a90 net/packet/af_packet.c:3612
 SYSC_setsockopt+0x4b8/0x570 net/socket.c:1849

Fixes: f6fb8f1 ("af-packet: TPACKET_V3 flexible buffer implementation.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 13, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 13, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 15, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 15, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 15, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 15, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 15, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 15, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 16, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 16, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 16, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 16, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 16, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 17, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 17, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 17, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 17, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 18, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 18, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 18, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 22, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 22, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 27, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 27, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 28, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 28, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 30, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 30, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 5, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 5, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 7, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 7, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 7, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 14, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 14, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 18, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 18, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 18, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 18, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 21, 2019
When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> #1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
jwrdegoede added a commit to jwrdegoede/linux-sunxi that referenced this issue Sep 21, 2019
tcpm_register_port() will call some of the fusb302 code's callbacks
wich in turn will call fusb302_log(). So we need to call
fusb302_debugfs_init() before we call tcpm_register_port().

This fixes the following warning, which was caused by the logbuffer_lock
not yet being initialized (which is done by fusb302_debugfs_init):

 DEBUG_LOCKS_WARN_ON(lock->magic != lock)
 WARNING: CPU: 0 PID: 1306 at kernel/locking/mutex.c:912 __mutex_lock+0x978/0x9a0
 Modules linked in: fusb302(+) tcpm pi3usb30532 typec bq24190_charger snd_soc_sst_cht_bsw_rt5645 mei_hdcp dwc3 intel_rapl_msr udc_core ulpi gpio_keys intel_powerclamp coretemp kvm_intel brcmfmac kvm brcmutil joydev cfg80211 wdat_wdt irqbypass pcspkr intel_cstate extcon_intel_cht_wc i2c_cht_wc(E) snd_intel_sst_acpi snd_intel_sst_core snd_soc_rt5645 snd_soc_sst_atom_hifi2_platform snd_soc_acpi_intel_match snd_soc_rl6231 snd_soc_acpi intel_xhci_usb_role_switch roles hci_uart snd_soc_core btqca mei_txe btrtl processor_thermal_device mei snd_hdmi_lpe_audio lpc_ich snd_compress btbcm intel_rapl_common ac97_bus dwc3_pci snd_pcm_dmaengine intel_soc_dts_iosf btintel snd_seq bluetooth snd_seq_device snd_pcm intel_cht_int33fe_musb snd_timer intel_cht_int33fe_typec intel_hid intel_cht_int33fe_common sparse_keymap snd ecdh_generic goodix rfkill soundcore ecc spi_pxa2xx_platform max17042_battery dw_dmac int3406_thermal dptf_power acpi_pad soc_button_array int3400_thermal int3403_thermal
  gpd_pocket_fan intel_int0002_vgpio int340x_thermal_zone acpi_thermal_rel dm_crypt mmc_block i915 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel i2c_algo_bit drm_kms_helper drm video sdhci_acpi sdhci mmc_core pwm_lpss_platform pwm_lpss i2c_dev
 CPU: 0 PID: 1306 Comm: systemd-udevd Tainted: G            E     5.3.0-rc4+ linux-sunxi#83
 Hardware name: Default string Default string/Default string, BIOS 5.11 06/28/2017
 RIP: 0010:__mutex_lock+0x978/0x9a0
 Code: c0 0f 84 26 f7 ff ff 44 8b 05 24 25 c8 00 45 85 c0 0f 85 16 f7 ff ff 48 c7 c6 da 55 2f ae 48 c7 c7 98 8c 2d ae e8 a0 f9 5c ff <0f> 0b e9 fc f6 ff ff 4c 89 f0 4d 89 fe 49 89 c7 e9 cf fa ff ff e8
 RSP: 0018:ffffb7a8c0523800 EFLAGS: 00010286
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246
 RBP: ffffb7a8c05238c0 R08: 0000000000000000 R09: 0000000000000000
 R10: ffffb7a8c0523648 R11: 0000000000000030 R12: 0000000000000000
 R13: ffffb7a8c0523990 R14: ffff9bf22f70c028 R15: ffff9bf22f70c360
 FS:  00007f39ca234940(0000) GS:ffff9bf237400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f1f108481a0 CR3: 0000000271f28000 CR4: 00000000001006f0
 Call Trace:
  ? find_held_lock+0x39/0x90
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  ? vsnprintf+0x3aa/0x4f0
  ? _fusb302_log+0x81/0x1d0 [fusb302]
  _fusb302_log+0x81/0x1d0 [fusb302]
 ...

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Oct 7, 2019
[ Upstream commit 232219b ]

When the kernel is build with lockdep support and the i2c-cht-wc driver is
used, the following warning is shown:

[   66.674334] ======================================================
[   66.674337] WARNING: possible circular locking dependency detected
[   66.674340] 5.3.0-rc4+ linux-sunxi#83 Not tainted
[   66.674342] ------------------------------------------------------
[   66.674345] systemd-udevd/1232 is trying to acquire lock:
[   66.674349] 00000000a74dab07 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}, at: regmap_write+0x31/0x70
[   66.674360]
               but task is already holding lock:
[   66.674362] 00000000d44a85b7 (i2c_register_adapter){+.+.}, at: i2c_smbus_xfer+0x49/0xf0
[   66.674370]
               which lock already depends on the new lock.

[   66.674371]
               the existing dependency chain (in reverse order) is:
[   66.674374]
               -> jwrdegoede#1 (i2c_register_adapter){+.+.}:
[   66.674381]        rt_mutex_lock_nested+0x46/0x60
[   66.674384]        i2c_smbus_xfer+0x49/0xf0
[   66.674387]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674391]        cht_wc_byte_reg_read+0x35/0x50
[   66.674394]        _regmap_read+0x63/0x1a0
[   66.674396]        _regmap_update_bits+0xa8/0xe0
[   66.674399]        regmap_update_bits_base+0x63/0xa0
[   66.674403]        regmap_irq_update_bits.isra.0+0x3b/0x50
[   66.674406]        regmap_add_irq_chip+0x592/0x7a0
[   66.674409]        devm_regmap_add_irq_chip+0x89/0xed
[   66.674412]        cht_wc_probe+0x102/0x158
[   66.674415]        i2c_device_probe+0x95/0x250
[   66.674419]        really_probe+0xf3/0x380
[   66.674422]        driver_probe_device+0x59/0xd0
[   66.674425]        device_driver_attach+0x53/0x60
[   66.674428]        __driver_attach+0x92/0x150
[   66.674431]        bus_for_each_dev+0x7d/0xc0
[   66.674434]        bus_add_driver+0x14d/0x1f0
[   66.674437]        driver_register+0x6d/0xb0
[   66.674440]        i2c_register_driver+0x45/0x80
[   66.674445]        do_one_initcall+0x60/0x2f4
[   66.674450]        kernel_init_freeable+0x20d/0x2b4
[   66.674453]        kernel_init+0xa/0x10c
[   66.674457]        ret_from_fork+0x3a/0x50
[   66.674459]
               -> #0 (intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock){+.+.}:
[   66.674465]        __lock_acquire+0xe07/0x1930
[   66.674468]        lock_acquire+0x9d/0x1a0
[   66.674472]        __mutex_lock+0xa8/0x9a0
[   66.674474]        regmap_write+0x31/0x70
[   66.674480]        cht_wc_i2c_adap_smbus_xfer+0x72/0x240 [i2c_cht_wc]
[   66.674483]        __i2c_smbus_xfer+0x1a3/0x640
[   66.674486]        i2c_smbus_xfer+0x67/0xf0
[   66.674489]        i2c_smbus_read_byte_data+0x45/0x70
[   66.674494]        bq24190_probe+0x26b/0x410 [bq24190_charger]
[   66.674497]        i2c_device_probe+0x189/0x250
[   66.674500]        really_probe+0xf3/0x380
[   66.674503]        driver_probe_device+0x59/0xd0
[   66.674506]        device_driver_attach+0x53/0x60
[   66.674509]        __driver_attach+0x92/0x150
[   66.674512]        bus_for_each_dev+0x7d/0xc0
[   66.674515]        bus_add_driver+0x14d/0x1f0
[   66.674518]        driver_register+0x6d/0xb0
[   66.674521]        i2c_register_driver+0x45/0x80
[   66.674524]        do_one_initcall+0x60/0x2f4
[   66.674528]        do_init_module+0x5c/0x230
[   66.674531]        load_module+0x2707/0x2a20
[   66.674534]        __do_sys_init_module+0x188/0x1b0
[   66.674537]        do_syscall_64+0x5c/0xb0
[   66.674541]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   66.674543]
               other info that might help us debug this:

[   66.674545]  Possible unsafe locking scenario:

[   66.674547]        CPU0                    CPU1
[   66.674548]        ----                    ----
[   66.674550]   lock(i2c_register_adapter);
[   66.674553]                                lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674556]                                lock(i2c_register_adapter);
[   66.674559]   lock(intel_soc_pmic_chtwc:167:(&cht_wc_regmap_cfg)->lock);
[   66.674561]
                *** DEADLOCK ***

The problem is that the CHT Whiskey Cove PMIC's builtin i2c-adapter is
itself a part of an i2c-client (the PMIC). This means that transfers done
through it take adapter->bus_lock twice, once for the parent i2c-adapter
and once for its own bus_lock. Lockdep does not like this nested locking.

To make lockdep happy in the case of busses with muxes, the i2c-core's
i2c_adapter_lock_bus function calls:

 rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter));

But i2c_adapter_depth only works when the direct parent of the adapter is
another adapter, as it is only meant for muxes. In this case there is an
i2c-client and MFD instantiated platform_device in the parent->child chain
between the 2 devices.

This commit overrides the default i2c_lock_operations, passing a hardcoded
depth of 1 to rt_mutex_lock_nested, making lockdep happy.

Note that if there were to be a mux attached to the i2c-wc-cht adapter,
this would break things again since the i2c-mux code expects the
root-adapter to have a locking depth of 0. But the i2c-wc-cht adapter
always has only 1 client directly attached in the form of the charger IC
paired with the CHT Whiskey Cove PMIC.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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