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pendings porting to 3.4 #48

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amery opened this issue Jul 3, 2012 · 2 comments
Closed

pendings porting to 3.4 #48

amery opened this issue Jul 3, 2012 · 2 comments

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@amery
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amery commented Jul 3, 2012

drivers that got broken:

  • drivers/net/wireless/rtl8192cu/ → allwinnerized version of drivers/net/wireless/rtlwifi/rtl8192cu

pending merges:

pending merges not even in 3.0-v2 tree:

@amery
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amery commented Jul 9, 2012

mali merged

@wingrime
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amery please update issue

@amery amery closed this as completed Sep 21, 2013
amery pushed a commit that referenced this issue Nov 12, 2013
As the new x86 CPU bootup printout format code maintainer, I am
taking immediate action to improve and clean (and thus indulge
my OCD) the reporting of the cores when coming up online.

Fix padding to a right-hand alignment, cleanup code and bind
reporting width to the max number of supported CPUs on the
system, like this:

 [    0.074509] smpboot: Booting Node   0, Processors:      #1  #2  #3  #4  #5  #6  #7 OK
 [    0.644008] smpboot: Booting Node   1, Processors:  #8  #9 #10 #11 #12 #13 #14 #15 OK
 [    1.245006] smpboot: Booting Node   2, Processors: #16 #17 #18 #19 #20 #21 #22 #23 OK
 [    1.864005] smpboot: Booting Node   3, Processors: #24 #25 #26 #27 #28 #29 #30 #31 OK
 [    2.489005] smpboot: Booting Node   4, Processors: #32 #33 #34 #35 #36 #37 #38 #39 OK
 [    3.093005] smpboot: Booting Node   5, Processors: #40 #41 #42 #43 #44 #45 #46 #47 OK
 [    3.698005] smpboot: Booting Node   6, Processors: #48 #49 #50 #51 #52 #53 #54 #55 OK
 [    4.304005] smpboot: Booting Node   7, Processors: #56 #57 #58 #59 #60 #61 #62 #63 OK
 [    4.961413] Brought up 64 CPUs

and this:

 [    0.072367] smpboot: Booting Node   0, Processors:    #1 #2 #3 #4 #5 #6 #7 OK
 [    0.686329] Brought up 8 CPUs

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Libin <huawei.libin@huawei.com>
Cc: wangyijing@huawei.com
Cc: fenghua.yu@intel.com
Cc: guohanjun@huawei.com
Cc: paul.gortmaker@windriver.com
Link: http://lkml.kernel.org/r/20130927143554.GF4422@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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 Jan 11, 2014
This reverts commit 9d046cc.

Commit 9d046cc marks all state tables with __initdata, but
the state table may be accessed when doing CPU online, which then
causing system crash as below:

[  204.188841] BUG: unable to handle kernel paging request at ffffffff8227cce8
[  204.196844] IP: [<ffffffff814aa1c0>] intel_idle_cpu_init+0x40/0x130
[  204.203996] PGD 1e11067 PUD 1e12063 PMD 455859063 PTE 800000000227c062
[  204.211638] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[  204.216975] Modules linked in: x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd gpio_ich microcode joydev sb_edac edac_core ipmi_si lpc_ich ipmi_msghandler lp tpm_tis parport wmi mac_hid acpi_pad hid_generic ixgbe isci usbhid dca hid libsas ptp ahci libahci scsi_transport_sas megaraid_sas pps_core mdio
[  204.262815] CPU: 11 PID: 1489 Comm: bash Not tainted 3.13.0-rc7+ #48
[  204.269993] Hardware name: Intel Corporation BRICKLAND/BRICKLAND, BIOS BRIVTIN1.86B.0047.L09.1312061514 12/06/2013
[  204.281646] task: ffff8804303a24a0 ti: ffff880440fac000 task.ti: ffff880440fac000
[  204.290311] RIP: 0010:[<ffffffff814aa1c0>]  [<ffffffff814aa1c0>] intel_idle_cpu_init+0x40/0x130
[  204.300184] RSP: 0018:ffff880440fadd28  EFLAGS: 00010286
[  204.306192] RAX: ffffffff8227cca0 RBX: ffffe8fff1a03400 RCX: 0000000000000007
[  204.314244] RDX: ffff88045f400000 RSI: 0000000000000009 RDI: 0000000000001120
[  204.322296] RBP: ffff880440fadd38 R08: 0000000000000000 R09: 0000000000000001
[  204.330411] R10: 0000000000000001 R11: 0000000000000000 R12: 000000000000001e
[  204.338482] R13: 00000000ffffffdb R14: 0000000000000001 R15: 0000000000000000
[  204.346743] FS:  00007f64f7b0c740(0000) GS:ffff88045ce00000(0000) knlGS:0000000000000000
[  204.355919] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  204.362449] CR2: ffffffff8227cce8 CR3: 0000000444ab0000 CR4: 00000000001407e0
[  204.370520] Stack:
[  204.372853]  000000000000001e ffffffff81f10240 ffff880440fadd50 ffffffff814aa307
[  204.381519]  ffffffff81ea80e0 ffff880440fadda0 ffffffff8185a230 0000000000000000
[  204.390196]  000000000000001e 0000000000000002 0000000000000002 0000000000000000
[  204.398856] Call Trace:
[  204.401683]  [<ffffffff814aa307>] cpu_hotplug_notify+0x57/0x70
[  204.408638]  [<ffffffff8185a230>] notifier_call_chain+0x100/0x150
[  204.415553]  [<ffffffff810a7dae>] __raw_notifier_call_chain+0xe/0x10
[  204.422772]  [<ffffffff81072163>] cpu_notify+0x23/0x50
[  204.428616]  [<ffffffff810723b2>] _cpu_up+0x132/0x1a0
[  204.434361]  [<ffffffff8107249d>] cpu_up+0x7d/0xa0
[  204.439819]  [<ffffffff81836c9c>] cpu_subsys_online+0x3c/0x90
[  204.446345]  [<ffffffff81554625>] device_online+0x45/0xa0
[  204.452471]  [<ffffffff815546ce>] online_store+0x4e/0x80
[  204.458511]  [<ffffffff815519a8>] dev_attr_store+0x18/0x30
[  204.464744]  [<ffffffff812a68f1>] sysfs_write_file+0x151/0x1c0
[  204.471681]  [<ffffffff81217ef1>] vfs_write+0xe1/0x160
[  204.477524]  [<ffffffff8121889c>] SyS_write+0x4c/0x90
[  204.483270]  [<ffffffff8185f2ed>] system_call_fastpath+0x1a/0x1f
[  204.490081] Code: 41 54 41 89 fc 8b 3d 48 25 85 01 53 48 8b 1d 30 25 85 01 48 03 1c c5 40 90 fb 81 48 8b 05 19 25 85 01 c7 43 0c 01 00 00 00 66 90 <48> 83 78 48 00 74 4f 41 83 c0 01 41 39 f0 7e 10 48 c7 c7 38 79
[  204.515723] RIP  [<ffffffff814aa1c0>] intel_idle_cpu_init+0x40/0x130
[  204.522996]  RSP <ffff880440fadd28>
[  204.526976] CR2: ffffffff8227cce8
[  204.530766] ---[ end trace 336f56cc3d1cfc8c ]---

Fixes: 9d046cc (intel_idle: mark states tables with __initdata tag)
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
amery pushed a commit that referenced this issue Jan 12, 2016
I get the splat below when modprobing/rmmoding EDAC drivers. It happens
because bus->name is invalid after bus_unregister() has run. The Code: section
below corresponds to:

  .loc 1 1108 0
  movq    672(%rbx), %rax # mci_1(D)->bus, mci_1(D)->bus
  .loc 1 1109 0
  popq    %rbx    #

  .loc 1 1108 0
  movq    (%rax), %rdi    # _7->name,
  jmp     kfree   #

and %rax has some funky stuff 2030203020312030 which looks a lot like
something walked over it.

Fix that by saving the name ptr before doing stuff to string it points to.

  general protection fault: 0000 [#1] SMP
  Modules linked in: ...
  CPU: 4 PID: 10318 Comm: modprobe Tainted: G          I EN  3.12.51-11-default+ #48
  Hardware name: HP ProLiant DL380 G7, BIOS P67 05/05/2011
  task: ffff880311320280 ti: ffff88030da3e000 task.ti: ffff88030da3e000
  RIP: 0010:[<ffffffffa019da92>]  [<ffffffffa019da92>] edac_unregister_sysfs+0x22/0x30 [edac_core]
  RSP: 0018:ffff88030da3fe28  EFLAGS: 00010292
  RAX: 2030203020312030 RBX: ffff880311b4e000 RCX: 000000000000095c
  RDX: 0000000000000001 RSI: ffff880327bb9600 RDI: 0000000000000286
  RBP: ffff880311b4e750 R08: 0000000000000000 R09: ffffffff81296110
  R10: 0000000000000400 R11: 0000000000000000 R12: ffff88030ba1ac68
  R13: 0000000000000001 R14: 00000000011b02f0 R15: 0000000000000000
  FS:  00007fc9bf8f5700(0000) GS:ffff8801a7c40000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: 0000000000403c90 CR3: 000000019ebdf000 CR4: 00000000000007e0
  Stack:
  Call Trace:
    i7core_unregister_mci.isra.9
    i7core_remove
    pci_device_remove
    __device_release_driver
    driver_detach
    bus_remove_driver
    pci_unregister_driver
    i7core_exit
    SyS_delete_module
    system_call_fastpath
    0x7fc9bf426536
  Code: 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 53 48 89 fb e8 52 2a 1f e1 48 8b bb a0 02 00 00 e8 46 59 1f e1 48 8b 83 a0 02 00 00 5b <48> 8b 38 e9 26 9a fe e0 66 0f 1f 44 00 00 66 66 66 66 90 48 8b
  RIP  [<ffffffffa019da92>] edac_unregister_sysfs+0x22/0x30 [edac_core]
   RSP <ffff88030da3fe28>

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: <stable@vger.kernel.org> # v3.6..
Fixes: 7a623c0 ("edac: rewrite the sysfs code to use struct device")
amery pushed a commit that referenced this issue Feb 7, 2016
This driver registers for extcon events as part of its probe, but
never unregisters them in case of error in the probe path.

There were multiple issues noticed due to this missing error handling.
One of them is random crashes if the regulators are not ready yet by the
time probe is invoked.

Ivan's previous attempt [1] to fix this issue, did not really address
all the failure cases like regualtor/get_irq failures.

[1] https://lkml.org/lkml/2015/9/7/62

Without this patch the kernel would carsh with log:
...
Unable to handle kernel paging request at virtual address 17d78410
pgd = ffffffc001a5c000
[17d78410] *pgd=00000000b6806003, *pud=00000000b6806003, *pmd=0000000000000000
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 6 Comm: kworker/u8:0 Not tainted 4.4.0+ #48
Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
Workqueue: deferwq deferred_probe_work_func
task: ffffffc03686e900 ti: ffffffc0368b0000 task.ti: ffffffc0368b0000
PC is at raw_notifier_chain_register+0x1c/0x44
LR is at extcon_register_notifier+0x88/0xc8
pc : [<ffffffc0000da43c>] lr : [<ffffffc000606298>] pstate: 80000085
sp : ffffffc0368b3a70
x29: ffffffc0368b3a70 x28: ffffffc03680c310
x27: ffffffc035518000 x26: ffffffc035518000
x25: ffffffc03bfa20e0 x24: ffffffc035580a18
x23: 0000000000000000 x22: ffffffc035518458
x21: ffffffc0355e9a60 x20: ffffffc035518000
x19: 0000000000000000 x18: 0000000000000028
x17: 0000000000000003 x16: ffffffc0018153c8
x15: 0000000000000001 x14: ffffffc03686f0f8
x13: ffffffc03686f0f8 x12: 0000000000000003
x11: 0000000000000001 x10: 0000000000000001
x9 : ffffffc03686f0f8 x8 : 0000e3872014c1a1
x7 : 0000000000000028 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000000
x3 : 00000000354fb170 x2 : 0000000017d78400
x1 : ffffffc0355e9a60 x0 : ffffffc0354fb268

Fixes: 	591fc11 ("usb: phy: msm: Use extcon framework for VBUS and ID detection")
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
amery pushed a commit that referenced this issue Dec 12, 2016
This is a regex converted version from the original:

	https://lkml.org/lkml/2016/5/19/461

Add basic support to recognise AArch64 assembly. This allows perf to
identify AArch64 instructions that branch to other parts within the
same function, thereby properly annotating them.

Rebased onto new cross-arch annotation bits:

	https://lkml.org/lkml/2016/11/25/546

Sample output:

security_file_permission  vmlinux
  5.80 │    ← ret                                                  ▒
       │70:   ldr    w0, [x21,#68]                                 ▒
  4.44 │    ↓ tbnz   d0                                            ▒
       │      mov    w0, #0x24                       // #36        ▒
  1.37 │      ands   w0, w22, w0                                   ▒
       │    ↑ b.eq   60                                            ▒
  1.37 │    ↓ tbnz   e4                                            ▒
       │      mov    w19, #0x20000                   // #131072    ▒
  1.02 │    ↓ tbz    ec                                            ▒
       │90:┌─→ldr    x3, [x21,#24]                                 ▒
  1.37 │   │  add    x21, x21, #0x10                               ▒
       │   │  mov    w2, w19                                       ▒
  1.02 │   │  mov    x0, x21                                       ▒
       │   │  mov    x1, x3                                        ▒
  1.71 │   │  ldr    x20, [x3,#48]                                 ▒
       │   │→ bl     __fsnotify_parent                             ▒
  0.68 │   │↑ cbnz   60                                            ▒
       │   │  mov    x2, x21                                       ▒
  1.37 │   │  mov    w1, w19                                       ▒
       │   │  mov    x0, x20                                       ▒
  0.68 │   │  mov    w5, #0x0                        // #0         ▒
       │   │  mov    x4, #0x0                        // #0         ▒
  1.71 │   │  mov    w3, #0x1                        // #1         ▒
       │   │→ bl     fsnotify                                      ▒
  1.37 │   │↑ b      60                                            ▒
       │d0:│  mov    w0, #0x0                        // #0         ▒
       │   │  ldp    x19, x20, [sp,#16]                            ▒
       │   │  ldp    x21, x22, [sp,#32]                            ▒
       │   │  ldp    x29, x30, [sp],#48                            ▒
       │   │← ret                                                  ▒
       │e4:│  mov    w19, #0x10000                   // #65536     ▒
       │   └──b      90                                            ◆
       │ec:   brk    #0x800                                        ▒
Press 'h' for help on key bindings

Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Chris Ryder <chris.ryder@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20161130092344.012e18e3e623bea395162f95@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
amery pushed a commit that referenced this issue Dec 13, 2016
If we execute the below steps without this patch:

  modprobe mpc85xx_edac [The first insmod, everything is well.]
  modprobe -r mpc85xx_edac
  modprobe mpc85xx_edac [insmod again, error happens.]

We would get the error messages as below:

  BUG: recent printk recursion!
  Oops: Kernel access of bad area, sig: 11 [#48]
  Modules linked in: mpc85xx_edac edac_core softdog [last unloaded: mpc85xx_edac]
  CPU: 5 PID: 14773 Comm: modprobe Tainted: G D C 4.8.3-rt2
   .vsnprintf
   .vscnprintf
   .vprintk_emit
   .printk
   .edac_pci_add_device
   .mpc85xx_pci_err_probe
   .platform_drv_probe
   .driver_probe_device
   .__driver_attach
   .bus_for_each_dev
   .driver_attach
   .bus_add_driver
   .driver_register
   .__platform_register_drivers
   .mpc85xx_mc_init
   .do_one_initcall
   .do_init_module
   .load_module
   .SyS_finit_module
   system_call

Address this by cleaning up properly when removing the platform driver.

Tested on a T4240QDS board.

Signed-off-by: Yanjiang Jin <yanjiang.jin@windriver.com>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: york.sun@nxp.com
Link: http://lkml.kernel.org/r/1479351380-17109-2-git-send-email-yanjiang.jin@windriver.com
[ Boris: massage commit message. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
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>
codekipper pushed a commit to codekipper/linux-sunxi that referenced this issue May 8, 2017
When the instruction right before the branch destination is
a 64 bit load immediate, we currently calculate the wrong
jump offset in the ctx->offset[] array as we only account
one instruction slot for the 64 bit load immediate although
it uses two BPF instructions. Fix it up by setting the offset
into the right slot after we incremented the index.

Before (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // linux-sunxi#3
  00000028:  d2800041  mov x1, #0x2 // linux-sunxi#2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  54ffff82  b.cs 0x00000020
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl linux-sunxi#16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl linux-sunxi#32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl linux-sunxi#48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl linux-sunxi#16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl linux-sunxi#32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl linux-sunxi#48
  [...]

After (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // linux-sunxi#3
  00000028:  d2800041  mov x1, #0x2 // linux-sunxi#2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  540000a2  b.cs 0x00000044
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl linux-sunxi#16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl linux-sunxi#32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl linux-sunxi#48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl linux-sunxi#16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl linux-sunxi#32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl linux-sunxi#48
  [...]

Also, add a couple of test cases to make sure JITs pass
this test. Tested on Cavium ThunderX ARMv8. The added
test cases all pass after the fix.

Fixes: 8eee539 ("arm64: bpf: fix out-of-bounds read in bpf2a64_offset()")
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Xi Wang <xi.wang@gmail.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 May 23, 2017
[ Upstream commit ddc665a ]

When the instruction right before the branch destination is
a 64 bit load immediate, we currently calculate the wrong
jump offset in the ctx->offset[] array as we only account
one instruction slot for the 64 bit load immediate although
it uses two BPF instructions. Fix it up by setting the offset
into the right slot after we incremented the index.

Before (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // jwrdegoede#3
  00000028:  d2800041  mov x1, #0x2 // jwrdegoede#2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  54ffff82  b.cs 0x00000020
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl linux-sunxi#16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl linux-sunxi#32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl linux-sunxi#48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl linux-sunxi#16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl linux-sunxi#32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl linux-sunxi#48
  [...]

After (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // jwrdegoede#3
  00000028:  d2800041  mov x1, #0x2 // jwrdegoede#2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  540000a2  b.cs 0x00000044
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl linux-sunxi#16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl linux-sunxi#32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl linux-sunxi#48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl linux-sunxi#16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl linux-sunxi#32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl linux-sunxi#48
  [...]

Also, add a couple of test cases to make sure JITs pass
this test. Tested on Cavium ThunderX ARMv8. The added
test cases all pass after the fix.

Fixes: 8eee539 ("arm64: bpf: fix out-of-bounds read in bpf2a64_offset()")
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Xi Wang <xi.wang@gmail.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 May 26, 2017
[ Upstream commit ddc665a ]

When the instruction right before the branch destination is
a 64 bit load immediate, we currently calculate the wrong
jump offset in the ctx->offset[] array as we only account
one instruction slot for the 64 bit load immediate although
it uses two BPF instructions. Fix it up by setting the offset
into the right slot after we incremented the index.

Before (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // jwrdegoede#3
  00000028:  d2800041  mov x1, #0x2 // jwrdegoede#2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  54ffff82  b.cs 0x00000020
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl linux-sunxi#16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl linux-sunxi#32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl linux-sunxi#48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl linux-sunxi#16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl linux-sunxi#32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl linux-sunxi#48
  [...]

After (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // jwrdegoede#3
  00000028:  d2800041  mov x1, #0x2 // jwrdegoede#2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  540000a2  b.cs 0x00000044
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl linux-sunxi#16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl linux-sunxi#32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl linux-sunxi#48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl linux-sunxi#16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl linux-sunxi#32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl linux-sunxi#48
  [...]

Also, add a couple of test cases to make sure JITs pass
this test. Tested on Cavium ThunderX ARMv8. The added
test cases all pass after the fix.

Fixes: 8eee539 ("arm64: bpf: fix out-of-bounds read in bpf2a64_offset()")
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Xi Wang <xi.wang@gmail.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 Jun 24, 2017
Commit bf5eb3d ("slub: separate out sysfs_slab_release() from
sysfs_slab_remove()") made slub sysfs file removals synchronous to
kmem_cache shutdown.

Unfortunately, this created a possible ABBA deadlock between slab_mutex
and sysfs draining mechanism triggering the following lockdep warning.

  ======================================================
  [ INFO: possible circular locking dependency detected ]
  4.10.0-test+ #48 Not tainted
  -------------------------------------------------------
  rmmod/1211 is trying to acquire lock:
   (s_active#120){++++.+}, at: [<ffffffff81308073>] kernfs_remove+0x23/0x40

  but task is already holding lock:
   (slab_mutex){+.+.+.}, at: [<ffffffff8120f691>] kmem_cache_destroy+0x41/0x2d0

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #1 (slab_mutex){+.+.+.}:
	 lock_acquire+0xf6/0x1f0
	 __mutex_lock+0x75/0x950
	 mutex_lock_nested+0x1b/0x20
	 slab_attr_store+0x75/0xd0
	 sysfs_kf_write+0x45/0x60
	 kernfs_fop_write+0x13c/0x1c0
	 __vfs_write+0x28/0x120
	 vfs_write+0xc8/0x1e0
	 SyS_write+0x49/0xa0
	 entry_SYSCALL_64_fastpath+0x1f/0xc2

  -> #0 (s_active#120){++++.+}:
	 __lock_acquire+0x10ed/0x1260
	 lock_acquire+0xf6/0x1f0
	 __kernfs_remove+0x254/0x320
	 kernfs_remove+0x23/0x40
	 sysfs_remove_dir+0x51/0x80
	 kobject_del+0x18/0x50
	 __kmem_cache_shutdown+0x3e6/0x460
	 kmem_cache_destroy+0x1fb/0x2d0
	 kvm_exit+0x2d/0x80 [kvm]
	 vmx_exit+0x19/0xa1b [kvm_intel]
	 SyS_delete_module+0x198/0x1f0
	 entry_SYSCALL_64_fastpath+0x1f/0xc2

  other info that might help us debug this:

   Possible unsafe locking scenario:

	 CPU0                    CPU1
	 ----                    ----
    lock(slab_mutex);
				 lock(s_active#120);
				 lock(slab_mutex);
    lock(s_active#120);

   *** DEADLOCK ***

  2 locks held by rmmod/1211:
   #0:  (cpu_hotplug.dep_map){++++++}, at: [<ffffffff810a7877>] get_online_cpus+0x37/0x80
   #1:  (slab_mutex){+.+.+.}, at: [<ffffffff8120f691>] kmem_cache_destroy+0x41/0x2d0

  stack backtrace:
  CPU: 3 PID: 1211 Comm: rmmod Not tainted 4.10.0-test+ #48
  Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012
  Call Trace:
   print_circular_bug+0x1be/0x210
   __lock_acquire+0x10ed/0x1260
   lock_acquire+0xf6/0x1f0
   __kernfs_remove+0x254/0x320
   kernfs_remove+0x23/0x40
   sysfs_remove_dir+0x51/0x80
   kobject_del+0x18/0x50
   __kmem_cache_shutdown+0x3e6/0x460
   kmem_cache_destroy+0x1fb/0x2d0
   kvm_exit+0x2d/0x80 [kvm]
   vmx_exit+0x19/0xa1b [kvm_intel]
   SyS_delete_module+0x198/0x1f0
   ? SyS_delete_module+0x5/0x1f0
   entry_SYSCALL_64_fastpath+0x1f/0xc2

It'd be the cleanest to deal with the issue by removing sysfs files
without holding slab_mutex before the rest of shutdown; however, given
the current code structure, it is pretty difficult to do so.

This patch punts sysfs file removal to a work item.  Before commit
bf5eb3d, the removal was punted to a RCU delayed work item which is
executed after release.  Now, we're punting to a different work item on
shutdown which still maintains the goal removing the sysfs files earlier
when destroying kmem_caches.

Link: http://lkml.kernel.org/r/20170620204512.GI21326@htj.duckdns.org
Fixes: bf5eb3d ("slub: separate out sysfs_slab_release() from sysfs_slab_remove()")
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.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 Nov 14, 2017
Lockdep warns about a potential deadlock:

[   66.782842] ======================================================
[   66.782888] WARNING: possible circular locking dependency detected
[   66.782937] 4.14.0-rc2-test-test+ #48 Not tainted
[   66.782983] ------------------------------------------------------
[   66.783052] umount/336 is trying to acquire lock:
[   66.783117]  (cpu_hotplug_lock.rw_sem){++++}, at: [<ffffffff81032395>] rdt_kill_sb+0x215/0x390
[   66.783193]
               but task is already holding lock:
[   66.783244]  (rdtgroup_mutex){+.+.}, at: [<ffffffff810321b6>] rdt_kill_sb+0x36/0x390
[   66.783305]
               which lock already depends on the new lock.

[   66.783364]
               the existing dependency chain (in reverse order) is:
[   66.783419]
               -> #3 (rdtgroup_mutex){+.+.}:
[   66.783467]        __lock_acquire+0x1293/0x13f0
[   66.783509]        lock_acquire+0xaf/0x220
[   66.783543]        __mutex_lock+0x71/0x9b0
[   66.783575]        mutex_lock_nested+0x1b/0x20
[   66.783610]        intel_rdt_online_cpu+0x3b/0x430
[   66.783649]        cpuhp_invoke_callback+0xab/0x8e0
[   66.783687]        cpuhp_thread_fun+0x7a/0x150
[   66.783722]        smpboot_thread_fn+0x1cc/0x270
[   66.783764]        kthread+0x16e/0x190
[   66.783794]        ret_from_fork+0x27/0x40
[   66.783825]
               -> #2 (cpuhp_state){+.+.}:
[   66.783870]        __lock_acquire+0x1293/0x13f0
[   66.783906]        lock_acquire+0xaf/0x220
[   66.783938]        cpuhp_issue_call+0x102/0x170
[   66.783974]        __cpuhp_setup_state_cpuslocked+0x154/0x2a0
[   66.784023]        __cpuhp_setup_state+0xc7/0x170
[   66.784061]        page_writeback_init+0x43/0x67
[   66.784097]        pagecache_init+0x43/0x4a
[   66.784131]        start_kernel+0x3ad/0x3f7
[   66.784165]        x86_64_start_reservations+0x2a/0x2c
[   66.784204]        x86_64_start_kernel+0x72/0x75
[   66.784241]        verify_cpu+0x0/0xfb
[   66.784270]
               -> #1 (cpuhp_state_mutex){+.+.}:
[   66.784319]        __lock_acquire+0x1293/0x13f0
[   66.784355]        lock_acquire+0xaf/0x220
[   66.784387]        __mutex_lock+0x71/0x9b0
[   66.784419]        mutex_lock_nested+0x1b/0x20
[   66.784454]        __cpuhp_setup_state_cpuslocked+0x52/0x2a0
[   66.784497]        __cpuhp_setup_state+0xc7/0x170
[   66.784535]        page_alloc_init+0x28/0x30
[   66.784569]        start_kernel+0x148/0x3f7
[   66.784602]        x86_64_start_reservations+0x2a/0x2c
[   66.784642]        x86_64_start_kernel+0x72/0x75
[   66.784678]        verify_cpu+0x0/0xfb
[   66.784707]
               -> #0 (cpu_hotplug_lock.rw_sem){++++}:
[   66.784759]        check_prev_add+0x32f/0x6e0
[   66.784794]        __lock_acquire+0x1293/0x13f0
[   66.784830]        lock_acquire+0xaf/0x220
[   66.784863]        cpus_read_lock+0x3d/0xb0
[   66.784896]        rdt_kill_sb+0x215/0x390
[   66.784930]        deactivate_locked_super+0x3e/0x70
[   66.784968]        deactivate_super+0x40/0x60
[   66.785003]        cleanup_mnt+0x3f/0x80
[   66.785034]        __cleanup_mnt+0x12/0x20
[   66.785070]        task_work_run+0x8b/0xc0
[   66.785103]        exit_to_usermode_loop+0x94/0xa0
[   66.786804]        syscall_return_slowpath+0xe8/0x150
[   66.788502]        entry_SYSCALL_64_fastpath+0xab/0xad
[   66.790194]
               other info that might help us debug this:

[   66.795139] Chain exists of:
                 cpu_hotplug_lock.rw_sem --> cpuhp_state --> rdtgroup_mutex

[   66.800035]  Possible unsafe locking scenario:

[   66.803267]        CPU0                    CPU1
[   66.804867]        ----                    ----
[   66.806443]   lock(rdtgroup_mutex);
[   66.808002]                                lock(cpuhp_state);
[   66.809565]                                lock(rdtgroup_mutex);
[   66.811110]   lock(cpu_hotplug_lock.rw_sem);
[   66.812608]
                *** DEADLOCK ***

[   66.816983] 2 locks held by umount/336:
[   66.818418]  #0:  (&type->s_umount_key#35){+.+.}, at: [<ffffffff81229738>] deactivate_super+0x38/0x60
[   66.819922]  #1:  (rdtgroup_mutex){+.+.}, at: [<ffffffff810321b6>] rdt_kill_sb+0x36/0x390

When the resctrl filesystem is unmounted the locks should be obtain in the
locks in the same order as was done when the cpus came online:

      cpu_hotplug_lock before rdtgroup_mutex.

This also requires to switch the static_branch_disable() calls to the
_cpulocked variant because now cpu hotplug lock is held already.

[ tglx: Switched to cpus_read_[un]lock ]

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Acked-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/cc292e76be073f7260604651711c47b09fd0dc81.1508490116.git.reinette.chatre@intel.com
amery pushed a commit that referenced this issue Jul 25, 2018
The level of struct nft_ctx is updated by nf_tables_check_loops().  That
is used to validate jumpstack depth. But jumpstack validation routine
doesn't update and validate recursively.  So, in some cases, chain depth
can be bigger than the NFT_JUMP_STACK_SIZE.

After this patch, The jumpstack validation routine is located in the
nft_chain_validate(). When new rules or new set elements are added, the
nft_table_validate() is called by the nf_tables_newrule and the
nf_tables_newsetelem. The nft_table_validate() calls the
nft_chain_validate() that visit all their children chains recursively.
So it can update depth of chain certainly.

Reproducer:
   %cat ./test.sh
   #!/bin/bash
   nft add table ip filter
   nft add chain ip filter input { type filter hook input priority 0\; }
   for ((i=0;i<20;i++)); do
	nft add chain ip filter a$i
   done

   nft add rule ip filter input jump a1

   for ((i=0;i<10;i++)); do
	nft add rule ip filter a$i jump a$((i+1))
   done

   for ((i=11;i<19;i++)); do
	nft add rule ip filter a$i jump a$((i+1))
   done

   nft add rule ip filter a10 jump a11

Result:
[  253.931782] WARNING: CPU: 1 PID: 0 at net/netfilter/nf_tables_core.c:186 nft_do_chain+0xacc/0xdf0 [nf_tables]
[  253.931915] Modules linked in: nf_tables nfnetlink ip_tables x_tables
[  253.932153] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.18.0-rc3+ #48
[  253.932153] RIP: 0010:nft_do_chain+0xacc/0xdf0 [nf_tables]
[  253.932153] Code: 83 f8 fb 0f 84 c7 00 00 00 e9 d0 00 00 00 83 f8 fd 74 0e 83 f8 ff 0f 84 b4 00 00 00 e9 bd 00 00 00 83 bd 64 fd ff ff 0f 76 09 <0f> 0b 31 c0 e9 bc 02 00 00 44 8b ad 64 fd
[  253.933807] RSP: 0018:ffff88011b807570 EFLAGS: 00010212
[  253.933807] RAX: 00000000fffffffd RBX: ffff88011b807660 RCX: 0000000000000000
[  253.933807] RDX: 0000000000000010 RSI: ffff880112b39d78 RDI: ffff88011b807670
[  253.933807] RBP: ffff88011b807850 R08: ffffed0023700ece R09: ffffed0023700ecd
[  253.933807] R10: ffff88011b80766f R11: ffffed0023700ece R12: ffff88011b807898
[  253.933807] R13: ffff880112b39d80 R14: ffff880112b39d60 R15: dffffc0000000000
[  253.933807] FS:  0000000000000000(0000) GS:ffff88011b800000(0000) knlGS:0000000000000000
[  253.933807] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  253.933807] CR2: 00000000014f1008 CR3: 000000006b216000 CR4: 00000000001006e0
[  253.933807] Call Trace:
[  253.933807]  <IRQ>
[  253.933807]  ? sched_clock_cpu+0x132/0x170
[  253.933807]  ? __nft_trace_packet+0x180/0x180 [nf_tables]
[  253.933807]  ? sched_clock_cpu+0x132/0x170
[  253.933807]  ? debug_show_all_locks+0x290/0x290
[  253.933807]  ? __lock_acquire+0x4835/0x4af0
[  253.933807]  ? inet_ehash_locks_alloc+0x1a0/0x1a0
[  253.933807]  ? unwind_next_frame+0x159e/0x1840
[  253.933807]  ? __read_once_size_nocheck.constprop.4+0x5/0x10
[  253.933807]  ? nft_do_chain_ipv4+0x197/0x1e0 [nf_tables]
[  253.933807]  ? nft_do_chain+0x5/0xdf0 [nf_tables]
[  253.933807]  nft_do_chain_ipv4+0x197/0x1e0 [nf_tables]
[  253.933807]  ? nft_do_chain_arp+0xb0/0xb0 [nf_tables]
[  253.933807]  ? __lock_is_held+0x9d/0x130
[  253.933807]  nf_hook_slow+0xc4/0x150
[  253.933807]  ip_local_deliver+0x28b/0x380
[  253.933807]  ? ip_call_ra_chain+0x3e0/0x3e0
[  253.933807]  ? ip_rcv_finish+0x1610/0x1610
[  253.933807]  ip_rcv+0xbcc/0xcc0
[  253.933807]  ? debug_show_all_locks+0x290/0x290
[  253.933807]  ? ip_local_deliver+0x380/0x380
[  253.933807]  ? __lock_is_held+0x9d/0x130
[  253.933807]  ? ip_local_deliver+0x380/0x380
[  253.933807]  __netif_receive_skb_core+0x1c9c/0x2240

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
amery pushed a commit that referenced this issue Jul 30, 2018
Dirk Gouders reported that two consecutive "make" invocations on an
already compiled tree will show alternating behaviors:

$ make
  CALL    scripts/checksyscalls.sh
  DESCEND  objtool
  CHK     include/generated/compile.h
  DATAREL arch/x86/boot/compressed/vmlinux
Kernel: arch/x86/boot/bzImage is ready  (#48)
  Building modules, stage 2.
  MODPOST 165 modules

$ make
  CALL    scripts/checksyscalls.sh
  DESCEND  objtool
  CHK     include/generated/compile.h
  LD      arch/x86/boot/compressed/vmlinux
  ZOFFSET arch/x86/boot/zoffset.h
  AS      arch/x86/boot/header.o
  LD      arch/x86/boot/setup.elf
  OBJCOPY arch/x86/boot/setup.bin
  OBJCOPY arch/x86/boot/vmlinux.bin
  BUILD   arch/x86/boot/bzImage
Setup is 15644 bytes (padded to 15872 bytes).
System is 6663 kB
CRC 3eb90f40
Kernel: arch/x86/boot/bzImage is ready  (#48)
  Building modules, stage 2.
  MODPOST 165 modules

He bisected it back to:

    commit 98f7852 ("x86/boot: Refuse to build with data relocations")

The root cause was the use of the "if_changed" kbuild function multiple
times for the same target. It was designed to only be used once per
target, otherwise it will effectively always trigger, flipping back and
forth between the two commands getting recorded by "if_changed". Instead,
this patch merges the two commands into a single function to get stable
build artifacts (i.e. .vmlinux.cmd), and a single build behavior.

Bisected-and-Reported-by: Dirk Gouders <dirk@gouders.net>
Fix-Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180724230827.GA37823@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Sep 5, 2018
[ Upstream commit 92a4728 ]

Dirk Gouders reported that two consecutive "make" invocations on an
already compiled tree will show alternating behaviors:

$ make
  CALL    scripts/checksyscalls.sh
  DESCEND  objtool
  CHK     include/generated/compile.h
  DATAREL arch/x86/boot/compressed/vmlinux
Kernel: arch/x86/boot/bzImage is ready  (linux-sunxi#48)
  Building modules, stage 2.
  MODPOST 165 modules

$ make
  CALL    scripts/checksyscalls.sh
  DESCEND  objtool
  CHK     include/generated/compile.h
  LD      arch/x86/boot/compressed/vmlinux
  ZOFFSET arch/x86/boot/zoffset.h
  AS      arch/x86/boot/header.o
  LD      arch/x86/boot/setup.elf
  OBJCOPY arch/x86/boot/setup.bin
  OBJCOPY arch/x86/boot/vmlinux.bin
  BUILD   arch/x86/boot/bzImage
Setup is 15644 bytes (padded to 15872 bytes).
System is 6663 kB
CRC 3eb90f40
Kernel: arch/x86/boot/bzImage is ready  (linux-sunxi#48)
  Building modules, stage 2.
  MODPOST 165 modules

He bisected it back to:

    commit 98f7852 ("x86/boot: Refuse to build with data relocations")

The root cause was the use of the "if_changed" kbuild function multiple
times for the same target. It was designed to only be used once per
target, otherwise it will effectively always trigger, flipping back and
forth between the two commands getting recorded by "if_changed". Instead,
this patch merges the two commands into a single function to get stable
build artifacts (i.e. .vmlinux.cmd), and a single build behavior.

Bisected-and-Reported-by: Dirk Gouders <dirk@gouders.net>
Fix-Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180724230827.GA37823@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
amery pushed a commit that referenced this issue Nov 9, 2018
Increase kasan instrumented kernel stack size from 32k to 64k. Other
architectures seems to get away with just doubling kernel stack size under
kasan, but on s390 this appears to be not enough due to bigger frame size.
The particular pain point is kasan inlined checks (CONFIG_KASAN_INLINE
vs CONFIG_KASAN_OUTLINE). With inlined checks one particular case hitting
stack overflow is fs sync on xfs filesystem:

 #0 [9a0681e8]  704 bytes  check_usage at 34b1fc
 #1 [9a0684a8]  432 bytes  check_usage at 34c710
 #2 [9a068658]  1048 bytes  validate_chain at 35044a
 #3 [9a068a70]  312 bytes  __lock_acquire at 3559fe
 #4 [9a068ba8]  440 bytes  lock_acquire at 3576ee
 #5 [9a068d60]  104 bytes  _raw_spin_lock at 21b44e0
 #6 [9a068dc8]  1992 bytes  enqueue_entity at 2dbf72
 #7 [9a069590]  1496 bytes  enqueue_task_fair at 2df5f0
 #8 [9a069b68]  64 bytes  ttwu_do_activate at 28f438
 #9 [9a069ba8]  552 bytes  try_to_wake_up at 298c4c
 #10 [9a069dd0]  168 bytes  wake_up_worker at 23f97c
 #11 [9a069e78]  200 bytes  insert_work at 23fc2e
 #12 [9a069f40]  648 bytes  __queue_work at 2487c0
 #13 [9a06a1c8]  200 bytes  __queue_delayed_work at 24db28
 #14 [9a06a290]  248 bytes  mod_delayed_work_on at 24de84
 #15 [9a06a388]  24 bytes  kblockd_mod_delayed_work_on at 153e2a0
 #16 [9a06a3a0]  288 bytes  __blk_mq_delay_run_hw_queue at 158168c
 #17 [9a06a4c0]  192 bytes  blk_mq_run_hw_queue at 1581a3c
 #18 [9a06a580]  184 bytes  blk_mq_sched_insert_requests at 15a2192
 #19 [9a06a638]  1024 bytes  blk_mq_flush_plug_list at 1590f3a
 #20 [9a06aa38]  704 bytes  blk_flush_plug_list at 1555028
 #21 [9a06acf8]  320 bytes  schedule at 219e476
 #22 [9a06ae38]  760 bytes  schedule_timeout at 21b0aac
 #23 [9a06b130]  408 bytes  wait_for_common at 21a1706
 #24 [9a06b2c8]  360 bytes  xfs_buf_iowait at fa1540
 #25 [9a06b430]  256 bytes  __xfs_buf_submit at fadae6
 #26 [9a06b530]  264 bytes  xfs_buf_read_map at fae3f6
 #27 [9a06b638]  656 bytes  xfs_trans_read_buf_map at 10ac9a8
 #28 [9a06b8c8]  304 bytes  xfs_btree_kill_root at e72426
 #29 [9a06b9f8]  288 bytes  xfs_btree_lookup_get_block at e7bc5e
 #30 [9a06bb18]  624 bytes  xfs_btree_lookup at e7e1a6
 #31 [9a06bd88]  2664 bytes  xfs_alloc_ag_vextent_near at dfa070
 #32 [9a06c7f0]  144 bytes  xfs_alloc_ag_vextent at dff3ca
 #33 [9a06c880]  1128 bytes  xfs_alloc_vextent at e05fce
 #34 [9a06cce8]  584 bytes  xfs_bmap_btalloc at e58342
 #35 [9a06cf30]  1336 bytes  xfs_bmapi_write at e618de
 #36 [9a06d468]  776 bytes  xfs_iomap_write_allocate at ff678e
 #37 [9a06d770]  720 bytes  xfs_map_blocks at f82af8
 #38 [9a06da40]  928 bytes  xfs_writepage_map at f83cd6
 #39 [9a06dde0]  320 bytes  xfs_do_writepage at f85872
 #40 [9a06df20]  1320 bytes  write_cache_pages at 73dfe8
 #41 [9a06e448]  208 bytes  xfs_vm_writepages at f7f892
 #42 [9a06e518]  88 bytes  do_writepages at 73fe6a
 #43 [9a06e570]  872 bytes  __writeback_single_inode at a20cb6
 #44 [9a06e8d8]  664 bytes  writeback_sb_inodes at a23be2
 #45 [9a06eb70]  296 bytes  __writeback_inodes_wb at a242e0
 #46 [9a06ec98]  928 bytes  wb_writeback at a2500e
 #47 [9a06f038]  848 bytes  wb_do_writeback at a260ae
 #48 [9a06f388]  536 bytes  wb_workfn at a28228
 #49 [9a06f5a0]  1088 bytes  process_one_work at 24a234
 #50 [9a06f9e0]  1120 bytes  worker_thread at 24ba26
 #51 [9a06fe40]  104 bytes  kthread at 26545a
 #52 [9a06fea8]             kernel_thread_starter at 21b6b62

To be able to increase the stack size to 64k reuse LLILL instruction
in __switch_to function to load 64k - STACK_FRAME_OVERHEAD - __PT_SIZE
(65192) value as unsigned.

Reported-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
amery pushed a commit that referenced this issue Nov 24, 2018
After commit 3c83dd5 ("wlcore: Add support for optional
wakeirq") landed upstream, I started seeing the following oops
on my HiKey board:

[    1.870279] Unable to handle kernel read from unreadable memory at virtual address 0000000000000010
[    1.870283] Mem abort info:
[    1.870287]   ESR = 0x96000005
[    1.870292]   Exception class = DABT (current EL), IL = 32 bits
[    1.870296]   SET = 0, FnV = 0
[    1.870299]   EA = 0, S1PTW = 0
[    1.870302] Data abort info:
[    1.870306]   ISV = 0, ISS = 0x00000005
[    1.870309]   CM = 0, WnR = 0
[    1.870312] [0000000000000010] user address but active_mm is swapper
[    1.870318] Internal error: Oops: 96000005 [#1] PREEMPT SMP
[    1.870327] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 4.19.0-05129-gb3d1e8e #48
[    1.870331] Hardware name: HiKey Development Board (DT)
[    1.870350] Workqueue: events_freezable mmc_rescan
[    1.870358] pstate: 60400005 (nZCv daif +PAN -UAO)
[    1.870366] pc : wl1271_probe+0x210/0x350
[    1.870371] lr : wl1271_probe+0x210/0x350
[    1.870374] sp : ffffff80080739b0
[    1.870377] x29: ffffff80080739b0 x28: 0000000000000000
[    1.870384] x27: 0000000000000000 x26: 0000000000000000
[    1.870391] x25: 0000000000000036 x24: ffffffc074ecb598
[    1.870398] x23: ffffffc07ffdce78 x22: ffffffc0744ed808
[    1.870404] x21: ffffffc074ecbb98 x20: ffffff8008ff9000
[    1.870411] x19: ffffffc0744ed800 x18: ffffff8008ff9a48
[    1.870418] x17: 0000000000000000 x16: 0000000000000000
[    1.870425] x15: ffffffc074ecb503 x14: ffffffffffffffff
[    1.870431] x13: ffffffc074ecb502 x12: 0000000000000030
[    1.870438] x11: 0101010101010101 x10: 0000000000000040
[    1.870444] x9 : ffffffc075400248 x8 : ffffffc075400270
[    1.870451] x7 : 0000000000000000 x6 : 0000000000000000
[    1.870457] x5 : 0000000000000000 x4 : 0000000000000000
[    1.870463] x3 : 0000000000000000 x2 : 0000000000000000
[    1.870469] x1 : 0000000000000028 x0 : 0000000000000000
[    1.870477] Process kworker/0:0 (pid: 5, stack limit = 0x(____ptrval____))
[    1.870480] Call trace:
[    1.870485]  wl1271_probe+0x210/0x350
[    1.870491]  sdio_bus_probe+0x100/0x128
[    1.870500]  really_probe+0x1a8/0x2b8
[    1.870506]  driver_probe_device+0x58/0x100
[    1.870511]  __device_attach_driver+0x94/0xd8
[    1.870517]  bus_for_each_drv+0x70/0xc8
[    1.870522]  __device_attach+0xe0/0x140
[    1.870527]  device_initial_probe+0x10/0x18
[    1.870532]  bus_probe_device+0x94/0xa0
[    1.870537]  device_add+0x374/0x5b8
[    1.870542]  sdio_add_func+0x60/0x88
[    1.870546]  mmc_attach_sdio+0x1b0/0x358
[    1.870551]  mmc_rescan+0x2cc/0x390
[    1.870558]  process_one_work+0x12c/0x320
[    1.870563]  worker_thread+0x48/0x458
[    1.870569]  kthread+0xf8/0x128
[    1.870575]  ret_from_fork+0x10/0x18
[    1.870583] Code: 92400c21 b2760021 a90687a2 97e95bf9 (f9400803)
[    1.870587] ---[ end trace 1e15f81d3c139ca9 ]---

It seems since we don't have a wakeirq value in the dts, the wakeirq
value in wl1271_probe() is zero, which then causes trouble in
irqd_get_trigger_type(irq_get_irq_data(wakeirq)).

This patch tries to address this by checking if wakeirq is zero,
and not trying to add it to the resources if that is the case.

Fixes: 3c83dd5 ("wlcore: Add support for optional wakeirq")
Cc: Tony Lindgren <tony@atomide.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Eyal Reizer <eyalr@ti.com>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: linux-wireless@vger.kernel.org
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Aug 10, 2019
After commit ddde3c1 ("vt: More locking checks") kdb / kgdb has
become useless because my console is filled with spews of:

WARNING: CPU: 0 PID: 0 at .../drivers/tty/vt/vt.c:3846 con_is_visible+0x50/0x74
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0-rc1+ linux-sunxi#48
Hardware name: Rockchip (Device Tree)
Backtrace:
[<c020ce9c>] (dump_backtrace) from [<c020d188>] (show_stack+0x20/0x24)
[<c020d168>] (show_stack) from [<c0a8fc14>] (dump_stack+0xb0/0xd0)
[<c0a8fb64>] (dump_stack) from [<c0232c58>] (__warn+0xec/0x11c)
[<c0232b6c>] (__warn) from [<c0232dc4>] (warn_slowpath_null+0x4c/0x58)
[<c0232d78>] (warn_slowpath_null) from [<c06338a0>] (con_is_visible+0x50/0x74)
[<c0633850>] (con_is_visible) from [<c0634078>] (con_scroll+0x108/0x1ac)
[<c0633f70>] (con_scroll) from [<c0634160>] (lf+0x44/0x88)
[<c063411c>] (lf) from [<c06363ec>] (vt_console_print+0x1a4/0x2bc)
[<c0636248>] (vt_console_print) from [<c02f628c>] (vkdb_printf+0x420/0x8a4)
[<c02f5e6c>] (vkdb_printf) from [<c02f6754>] (kdb_printf+0x44/0x60)
[<c02f6714>] (kdb_printf) from [<c02fa6f4>] (kdb_main_loop+0xf4/0x6e0)
[<c02fa600>] (kdb_main_loop) from [<c02fd5f0>] (kdb_stub+0x268/0x398)
[<c02fd388>] (kdb_stub) from [<c02f3ba0>] (kgdb_cpu_enter+0x1f8/0x674)
[<c02f39a8>] (kgdb_cpu_enter) from [<c02f4330>] (kgdb_handle_exception+0x1c4/0x1fc)
[<c02f416c>] (kgdb_handle_exception) from [<c0210fe0>] (kgdb_compiled_brk_fn+0x30/0x3c)
[<c0210fb0>] (kgdb_compiled_brk_fn) from [<c020d7ac>] (do_undefinstr+0x180/0x1a0)
[<c020d62c>] (do_undefinstr) from [<c0201b44>] (__und_svc_finish+0x0/0x3c)
...
[<c02f3224>] (kgdb_breakpoint) from [<c02f3310>] (sysrq_handle_dbg+0x58/0x6c)
[<c02f32b8>] (sysrq_handle_dbg) from [<c062abf0>] (__handle_sysrq+0xac/0x154)

Let's disable this warning when we're in kgdb to avoid the spew.  The
whole system is stopped when we're in kgdb so we can't exactly wait
for someone else to drop the lock.  Presumably the best we can do is
to disable the warning and hope for the best.

Fixes: ddde3c1 ("vt: More locking checks")
Cc: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20190725183551.169208-1-dianders@chromium.org
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 21, 2020
[ Upstream commit dd09fad ]

Commit:

  3a6b6c6 ("efi: Make EFI_MEMORY_ATTRIBUTES_TABLE initialization common across all architectures")

moved the call to efi_memattr_init() from ARM specific to the generic
EFI init code, in order to be able to apply the restricted permissions
described in that table on x86 as well.

We never enabled this feature fully on i386, and so mapping and
reserving this table is pointless. However, due to the early call to
memblock_reserve(), the memory bookkeeping gets confused to the point
where it produces the splat below when we try to map the memory later
on:

  ------------[ cut here ]------------
  ioremap on RAM at 0x3f251000 - 0x3fa1afff
  WARNING: CPU: 0 PID: 0 at arch/x86/mm/ioremap.c:166 __ioremap_caller ...
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.20.0 linux-sunxi#48
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
  EIP: __ioremap_caller.constprop.0+0x249/0x260
  Code: 90 0f b7 05 4e 38 40 de 09 45 e0 e9 09 ff ff ff 90 8d 45 ec c6 05 ...
  EAX: 00000029 EBX: 00000000 ECX: de59c228 EDX: 00000001
  ESI: 3f250fff EDI: 00000000 EBP: de3edf20 ESP: de3edee0
  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00200296
  CR0: 80050033 CR2: ffd17000 CR3: 1e58c000 CR4: 00040690
  Call Trace:
   ioremap_cache+0xd/0x10
   ? old_map_region+0x72/0x9d
   old_map_region+0x72/0x9d
   efi_map_region+0x8/0xa
   efi_enter_virtual_mode+0x260/0x43b
   start_kernel+0x329/0x3aa
   i386_start_kernel+0xa7/0xab
   startup_32_smp+0x164/0x168
  ---[ end trace e15ccf6b9f356833 ]---

Let's work around this by disregarding the memory attributes table
altogether on i386, which does not result in a loss of functionality
or protection, given that we never consumed the contents.

Fixes: 3a6b6c6 ("efi: Make EFI_MEMORY_ATTRIBUTES_TABLE ... ")
Tested-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200304165917.5893-1-ardb@kernel.org
Link: https://lore.kernel.org/r/20200308080859.21568-21-ardb@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue May 4, 2020
…f fs_info::journal_info

[BUG]
One run of btrfs/063 triggered the following lockdep warning:
  ============================================
  WARNING: possible recursive locking detected
  5.6.0-rc7-custom+ linux-sunxi#48 Not tainted
  --------------------------------------------
  kworker/u24:0/7 is trying to acquire lock:
  ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]

  but task is already holding lock:
  ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(sb_internal#2);
    lock(sb_internal#2);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  4 locks held by kworker/u24:0/7:
   #0: ffff88817b495948 ((wq_completion)btrfs-endio-write){+.+.}, at: process_one_work+0x557/0xb80
   #1: ffff888189ea7db8 ((work_completion)(&work->normal_work)){+.+.}, at: process_one_work+0x557/0xb80
   #2: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]
   #3: ffff888174ca4da8 (&fs_info->reloc_mutex){+.+.}, at: btrfs_record_root_in_trans+0x83/0xd0 [btrfs]

  stack backtrace:
  CPU: 0 PID: 7 Comm: kworker/u24:0 Not tainted 5.6.0-rc7-custom+ linux-sunxi#48
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
  Call Trace:
   dump_stack+0xc2/0x11a
   __lock_acquire.cold+0xce/0x214
   lock_acquire+0xe6/0x210
   __sb_start_write+0x14e/0x290
   start_transaction+0x66c/0x890 [btrfs]
   btrfs_join_transaction+0x1d/0x20 [btrfs]
   find_free_extent+0x1504/0x1a50 [btrfs]
   btrfs_reserve_extent+0xd5/0x1f0 [btrfs]
   btrfs_alloc_tree_block+0x1ac/0x570 [btrfs]
   btrfs_copy_root+0x213/0x580 [btrfs]
   create_reloc_root+0x3bd/0x470 [btrfs]
   btrfs_init_reloc_root+0x2d2/0x310 [btrfs]
   record_root_in_trans+0x191/0x1d0 [btrfs]
   btrfs_record_root_in_trans+0x90/0xd0 [btrfs]
   start_transaction+0x16e/0x890 [btrfs]
   btrfs_join_transaction+0x1d/0x20 [btrfs]
   btrfs_finish_ordered_io+0x55d/0xcd0 [btrfs]
   finish_ordered_fn+0x15/0x20 [btrfs]
   btrfs_work_helper+0x116/0x9a0 [btrfs]
   process_one_work+0x632/0xb80
   worker_thread+0x80/0x690
   kthread+0x1a3/0x1f0
   ret_from_fork+0x27/0x50

It's pretty hard to reproduce, only one hit so far.

[CAUSE]
This is because we're calling btrfs_join_transaction() without re-using
the current running one:

btrfs_finish_ordered_io()
|- btrfs_join_transaction()		<<< Call #1
   |- btrfs_record_root_in_trans()
      |- btrfs_reserve_extent()
	 |- btrfs_join_transaction()	<<< Call #2

Normally such btrfs_join_transaction() call should re-use the existing
one, without trying to re-start a transaction.

But the problem is, in btrfs_join_transaction() call #1, we call
btrfs_record_root_in_trans() before initializing current::journal_info.

And in btrfs_join_transaction() call #2, we're relying on
current::journal_info to avoid such deadlock.

[FIX]
Call btrfs_record_root_in_trans() after we have initialized
current::journal_info.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue May 6, 2020
…f fs_info::journal_info

commit fcc9973 upstream.

[BUG]
One run of btrfs/063 triggered the following lockdep warning:
  ============================================
  WARNING: possible recursive locking detected
  5.6.0-rc7-custom+ linux-sunxi#48 Not tainted
  --------------------------------------------
  kworker/u24:0/7 is trying to acquire lock:
  ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]

  but task is already holding lock:
  ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(sb_internal#2);
    lock(sb_internal#2);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  4 locks held by kworker/u24:0/7:
   #0: ffff88817b495948 ((wq_completion)btrfs-endio-write){+.+.}, at: process_one_work+0x557/0xb80
   jwrdegoede#1: ffff888189ea7db8 ((work_completion)(&work->normal_work)){+.+.}, at: process_one_work+0x557/0xb80
   jwrdegoede#2: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]
   jwrdegoede#3: ffff888174ca4da8 (&fs_info->reloc_mutex){+.+.}, at: btrfs_record_root_in_trans+0x83/0xd0 [btrfs]

  stack backtrace:
  CPU: 0 PID: 7 Comm: kworker/u24:0 Not tainted 5.6.0-rc7-custom+ linux-sunxi#48
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
  Call Trace:
   dump_stack+0xc2/0x11a
   __lock_acquire.cold+0xce/0x214
   lock_acquire+0xe6/0x210
   __sb_start_write+0x14e/0x290
   start_transaction+0x66c/0x890 [btrfs]
   btrfs_join_transaction+0x1d/0x20 [btrfs]
   find_free_extent+0x1504/0x1a50 [btrfs]
   btrfs_reserve_extent+0xd5/0x1f0 [btrfs]
   btrfs_alloc_tree_block+0x1ac/0x570 [btrfs]
   btrfs_copy_root+0x213/0x580 [btrfs]
   create_reloc_root+0x3bd/0x470 [btrfs]
   btrfs_init_reloc_root+0x2d2/0x310 [btrfs]
   record_root_in_trans+0x191/0x1d0 [btrfs]
   btrfs_record_root_in_trans+0x90/0xd0 [btrfs]
   start_transaction+0x16e/0x890 [btrfs]
   btrfs_join_transaction+0x1d/0x20 [btrfs]
   btrfs_finish_ordered_io+0x55d/0xcd0 [btrfs]
   finish_ordered_fn+0x15/0x20 [btrfs]
   btrfs_work_helper+0x116/0x9a0 [btrfs]
   process_one_work+0x632/0xb80
   worker_thread+0x80/0x690
   kthread+0x1a3/0x1f0
   ret_from_fork+0x27/0x50

It's pretty hard to reproduce, only one hit so far.

[CAUSE]
This is because we're calling btrfs_join_transaction() without re-using
the current running one:

btrfs_finish_ordered_io()
|- btrfs_join_transaction()		<<< Call jwrdegoede#1
   |- btrfs_record_root_in_trans()
      |- btrfs_reserve_extent()
	 |- btrfs_join_transaction()	<<< Call jwrdegoede#2

Normally such btrfs_join_transaction() call should re-use the existing
one, without trying to re-start a transaction.

But the problem is, in btrfs_join_transaction() call jwrdegoede#1, we call
btrfs_record_root_in_trans() before initializing current::journal_info.

And in btrfs_join_transaction() call jwrdegoede#2, we're relying on
current::journal_info to avoid such deadlock.

[FIX]
Call btrfs_record_root_in_trans() after we have initialized
current::journal_info.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Jul 29, 2020
commit f4c23a1 upstream.

I got null-ptr-deref in serial8250_start_tx():

[   78.114630] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[   78.123778] Mem abort info:
[   78.126560]   ESR = 0x86000007
[   78.129603]   EC = 0x21: IABT (current EL), IL = 32 bits
[   78.134891]   SET = 0, FnV = 0
[   78.137933]   EA = 0, S1PTW = 0
[   78.141064] user pgtable: 64k pages, 48-bit VAs, pgdp=00000027d41a8600
[   78.147562] [0000000000000000] pgd=00000027893f0003, p4d=00000027893f0003, pud=00000027893f0003, pmd=00000027c9a20003, pte=0000000000000000
[   78.160029] Internal error: Oops: 86000007 [jwrdegoede#1] SMP
[   78.164886] Modules linked in: sunrpc vfat fat aes_ce_blk crypto_simd cryptd aes_ce_cipher crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce ses enclosure sg sbsa_gwdt ipmi_ssif spi_dw_mmio sch_fq_codel vhost_net tun vhost vhost_iotlb tap ip_tables ext4 mbcache jbd2 ahci hisi_sas_v3_hw libahci hisi_sas_main libsas hns3 scsi_transport_sas hclge libata megaraid_sas ipmi_si hnae3 ipmi_devintf ipmi_msghandler br_netfilter bridge stp llc nvme nvme_core xt_sctp sctp libcrc32c dm_mod nbd
[   78.207383] CPU: 11 PID: 23258 Comm: null-ptr Not tainted 5.8.0-rc6+ linux-sunxi#48
[   78.214056] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B210.01 03/12/2020
[   78.222888] pstate: 80400089 (Nzcv daIf +PAN -UAO BTYPE=--)
[   78.228435] pc : 0x0
[   78.230618] lr : serial8250_start_tx+0x160/0x260
[   78.235215] sp : ffff800062eefb80
[   78.238517] x29: ffff800062eefb80 x28: 0000000000000fff
[   78.243807] x27: ffff800062eefd80 x26: ffff202fd83b3000
[   78.249098] x25: ffff800062eefd80 x24: ffff202fd83b3000
[   78.254388] x23: ffff002fc5e50be8 x22: 0000000000000002
[   78.259679] x21: 0000000000000001 x20: 0000000000000000
[   78.264969] x19: ffffa688827eecc8 x18: 0000000000000000
[   78.270259] x17: 0000000000000000 x16: 0000000000000000
[   78.275550] x15: ffffa68881bc67a8 x14: 00000000000002e6
[   78.280841] x13: ffffa68881bc67a8 x12: 000000000000c539
[   78.286131] x11: d37a6f4de9bd37a7 x10: ffffa68881cccff0
[   78.291421] x9 : ffffa68881bc6000 x8 : ffffa688819daa88
[   78.296711] x7 : ffffa688822a0f20 x6 : ffffa688819e0000
[   78.302002] x5 : ffff800062eef9d0 x4 : ffffa68881e707a8
[   78.307292] x3 : 0000000000000000 x2 : 0000000000000002
[   78.312582] x1 : 0000000000000001 x0 : ffffa688827eecc8
[   78.317873] Call trace:
[   78.320312]  0x0
[   78.322147]  __uart_start.isra.9+0x64/0x78
[   78.326229]  uart_start+0xb8/0x1c8
[   78.329620]  uart_flush_chars+0x24/0x30
[   78.333442]  n_tty_receive_buf_common+0x7b0/0xc30
[   78.338128]  n_tty_receive_buf+0x44/0x2c8
[   78.342122]  tty_ioctl+0x348/0x11f8
[   78.345599]  ksys_ioctl+0xd8/0xf8
[   78.348903]  __arm64_sys_ioctl+0x2c/0xc8
[   78.352812]  el0_svc_common.constprop.2+0x88/0x1b0
[   78.357583]  do_el0_svc+0x44/0xd0
[   78.360887]  el0_sync_handler+0x14c/0x1d0
[   78.364880]  el0_sync+0x140/0x180
[   78.368185] Code: bad PC value

SERIAL_PORT_DFNS is not defined on each arch, if it's not defined,
serial8250_set_defaults() won't be called in serial8250_isa_init_ports(),
so the p->serial_in pointer won't be initialized, and it leads a null-ptr-deref.
Fix this problem by calling serial8250_set_defaults() after init uart port.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200721143852.4058352-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue May 14, 2021
[ Upstream commit 0f20615 ]

Fix BPF_CORE_READ_BITFIELD() macro used for reading CO-RE-relocatable
bitfields. Missing breaks in a switch caused 8-byte reads always. This can
confuse libbpf because it does strict checks that memory load size corresponds
to the original size of the field, which in this case quite often would be
wrong.

After fixing that, we run into another problem, which quite subtle, so worth
documenting here. The issue is in Clang optimization and CO-RE relocation
interactions. Without that asm volatile construct (also known as
barrier_var()), Clang will re-order BYTE_OFFSET and BYTE_SIZE relocations and
will apply BYTE_OFFSET 4 times for each switch case arm. This will result in
the same error from libbpf about mismatch of memory load size and original
field size. I.e., if we were reading u32, we'd still have *(u8 *), *(u16 *),
*(u32 *), and *(u64 *) memory loads, three of which will fail. Using
barrier_var() forces Clang to apply BYTE_OFFSET relocation first (and once) to
calculate p, after which value of p is used without relocation in each of
switch case arms, doing appropiately-sized memory load.

Here's the list of relevant relocations and pieces of generated BPF code
before and after this patch for test_core_reloc_bitfields_direct selftests.

BEFORE
=====
 linux-sunxi#45: core_reloc: insn linux-sunxi#160 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32
 linux-sunxi#46: core_reloc: insn linux-sunxi#167 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 linux-sunxi#47: core_reloc: insn linux-sunxi#174 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 linux-sunxi#48: core_reloc: insn linux-sunxi#178 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 linux-sunxi#49: core_reloc: insn linux-sunxi#182 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32

     157:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     159:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     160:       b7 02 00 00 04 00 00 00 r2 = 4
; BYTE_SIZE relocation here                 ^^^
     161:       66 02 07 00 03 00 00 00 if w2 s> 3 goto +7 <LBB0_63>
     162:       16 02 0d 00 01 00 00 00 if w2 == 1 goto +13 <LBB0_65>
     163:       16 02 01 00 02 00 00 00 if w2 == 2 goto +1 <LBB0_66>
     164:       05 00 12 00 00 00 00 00 goto +18 <LBB0_69>

0000000000000528 <LBB0_66>:
     165:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     167:       69 11 08 00 00 00 00 00 r1 = *(u16 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     168:       05 00 0e 00 00 00 00 00 goto +14 <LBB0_69>

0000000000000548 <LBB0_63>:
     169:       16 02 0a 00 04 00 00 00 if w2 == 4 goto +10 <LBB0_67>
     170:       16 02 01 00 08 00 00 00 if w2 == 8 goto +1 <LBB0_68>
     171:       05 00 0b 00 00 00 00 00 goto +11 <LBB0_69>

0000000000000560 <LBB0_68>:
     172:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     174:       79 11 08 00 00 00 00 00 r1 = *(u64 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     175:       05 00 07 00 00 00 00 00 goto +7 <LBB0_69>

0000000000000580 <LBB0_65>:
     176:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     178:       71 11 08 00 00 00 00 00 r1 = *(u8 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     179:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

00000000000005a0 <LBB0_67>:
     180:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     182:       61 11 08 00 00 00 00 00 r1 = *(u32 *)(r1 + 8)
; BYTE_OFFSET relo here w/ RIGHT size        ^^^^^^^^^^^^^^^^

00000000000005b8 <LBB0_69>:
     183:       67 01 00 00 20 00 00 00 r1 <<= 32
     184:       b7 02 00 00 00 00 00 00 r2 = 0
     185:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     186:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     187:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000005e0 <LBB0_71>:
     188:       77 01 00 00 20 00 00 00 r1 >>= 32

AFTER
=====

 linux-sunxi#30: core_reloc: insn linux-sunxi#132 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 linux-sunxi#31: core_reloc: insn linux-sunxi#134 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32

     129:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     131:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     132:       b7 01 00 00 08 00 00 00 r1 = 8
; BYTE_OFFSET relo here                     ^^^
; no size check for non-memory dereferencing instructions
     133:       0f 12 00 00 00 00 00 00 r2 += r1
     134:       b7 03 00 00 04 00 00 00 r3 = 4
; BYTE_SIZE relocation here                 ^^^
     135:       66 03 05 00 03 00 00 00 if w3 s> 3 goto +5 <LBB0_63>
     136:       16 03 09 00 01 00 00 00 if w3 == 1 goto +9 <LBB0_65>
     137:       16 03 01 00 02 00 00 00 if w3 == 2 goto +1 <LBB0_66>
     138:       05 00 0a 00 00 00 00 00 goto +10 <LBB0_69>

0000000000000458 <LBB0_66>:
     139:       69 21 00 00 00 00 00 00 r1 = *(u16 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     140:       05 00 08 00 00 00 00 00 goto +8 <LBB0_69>

0000000000000468 <LBB0_63>:
     141:       16 03 06 00 04 00 00 00 if w3 == 4 goto +6 <LBB0_67>
     142:       16 03 01 00 08 00 00 00 if w3 == 8 goto +1 <LBB0_68>
     143:       05 00 05 00 00 00 00 00 goto +5 <LBB0_69>

0000000000000480 <LBB0_68>:
     144:       79 21 00 00 00 00 00 00 r1 = *(u64 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     145:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

0000000000000490 <LBB0_65>:
     146:       71 21 00 00 00 00 00 00 r1 = *(u8 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     147:       05 00 01 00 00 00 00 00 goto +1 <LBB0_69>

00000000000004a0 <LBB0_67>:
     148:       61 21 00 00 00 00 00 00 r1 = *(u32 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^

00000000000004a8 <LBB0_69>:
     149:       67 01 00 00 20 00 00 00 r1 <<= 32
     150:       b7 02 00 00 00 00 00 00 r2 = 0
     151:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     152:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     153:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000004d0 <LBB0_71>:
     154:       77 01 00 00 20 00 00 00 r1 >>= 323

Fixes: ee26dad ("libbpf: Add support for relocatable bitfields")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/20210426192949.416837-4-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue May 18, 2021
[ Upstream commit 0f20615 ]

Fix BPF_CORE_READ_BITFIELD() macro used for reading CO-RE-relocatable
bitfields. Missing breaks in a switch caused 8-byte reads always. This can
confuse libbpf because it does strict checks that memory load size corresponds
to the original size of the field, which in this case quite often would be
wrong.

After fixing that, we run into another problem, which quite subtle, so worth
documenting here. The issue is in Clang optimization and CO-RE relocation
interactions. Without that asm volatile construct (also known as
barrier_var()), Clang will re-order BYTE_OFFSET and BYTE_SIZE relocations and
will apply BYTE_OFFSET 4 times for each switch case arm. This will result in
the same error from libbpf about mismatch of memory load size and original
field size. I.e., if we were reading u32, we'd still have *(u8 *), *(u16 *),
*(u32 *), and *(u64 *) memory loads, three of which will fail. Using
barrier_var() forces Clang to apply BYTE_OFFSET relocation first (and once) to
calculate p, after which value of p is used without relocation in each of
switch case arms, doing appropiately-sized memory load.

Here's the list of relevant relocations and pieces of generated BPF code
before and after this patch for test_core_reloc_bitfields_direct selftests.

BEFORE
=====
 linux-sunxi#45: core_reloc: insn linux-sunxi#160 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32
 linux-sunxi#46: core_reloc: insn linux-sunxi#167 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 linux-sunxi#47: core_reloc: insn linux-sunxi#174 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 linux-sunxi#48: core_reloc: insn linux-sunxi#178 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 linux-sunxi#49: core_reloc: insn linux-sunxi#182 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32

     157:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     159:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     160:       b7 02 00 00 04 00 00 00 r2 = 4
; BYTE_SIZE relocation here                 ^^^
     161:       66 02 07 00 03 00 00 00 if w2 s> 3 goto +7 <LBB0_63>
     162:       16 02 0d 00 01 00 00 00 if w2 == 1 goto +13 <LBB0_65>
     163:       16 02 01 00 02 00 00 00 if w2 == 2 goto +1 <LBB0_66>
     164:       05 00 12 00 00 00 00 00 goto +18 <LBB0_69>

0000000000000528 <LBB0_66>:
     165:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     167:       69 11 08 00 00 00 00 00 r1 = *(u16 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     168:       05 00 0e 00 00 00 00 00 goto +14 <LBB0_69>

0000000000000548 <LBB0_63>:
     169:       16 02 0a 00 04 00 00 00 if w2 == 4 goto +10 <LBB0_67>
     170:       16 02 01 00 08 00 00 00 if w2 == 8 goto +1 <LBB0_68>
     171:       05 00 0b 00 00 00 00 00 goto +11 <LBB0_69>

0000000000000560 <LBB0_68>:
     172:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     174:       79 11 08 00 00 00 00 00 r1 = *(u64 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     175:       05 00 07 00 00 00 00 00 goto +7 <LBB0_69>

0000000000000580 <LBB0_65>:
     176:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     178:       71 11 08 00 00 00 00 00 r1 = *(u8 *)(r1 + 8)
; BYTE_OFFSET relo here w/ WRONG size        ^^^^^^^^^^^^^^^^
     179:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

00000000000005a0 <LBB0_67>:
     180:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
     182:       61 11 08 00 00 00 00 00 r1 = *(u32 *)(r1 + 8)
; BYTE_OFFSET relo here w/ RIGHT size        ^^^^^^^^^^^^^^^^

00000000000005b8 <LBB0_69>:
     183:       67 01 00 00 20 00 00 00 r1 <<= 32
     184:       b7 02 00 00 00 00 00 00 r2 = 0
     185:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     186:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     187:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000005e0 <LBB0_71>:
     188:       77 01 00 00 20 00 00 00 r1 >>= 32

AFTER
=====

 linux-sunxi#30: core_reloc: insn linux-sunxi#132 --> [5] + 0:5: byte_off --> struct core_reloc_bitfields.u32
 linux-sunxi#31: core_reloc: insn linux-sunxi#134 --> [5] + 0:5: byte_sz --> struct core_reloc_bitfields.u32

     129:       18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0 ll
     131:       7b 12 20 01 00 00 00 00 *(u64 *)(r2 + 288) = r1
     132:       b7 01 00 00 08 00 00 00 r1 = 8
; BYTE_OFFSET relo here                     ^^^
; no size check for non-memory dereferencing instructions
     133:       0f 12 00 00 00 00 00 00 r2 += r1
     134:       b7 03 00 00 04 00 00 00 r3 = 4
; BYTE_SIZE relocation here                 ^^^
     135:       66 03 05 00 03 00 00 00 if w3 s> 3 goto +5 <LBB0_63>
     136:       16 03 09 00 01 00 00 00 if w3 == 1 goto +9 <LBB0_65>
     137:       16 03 01 00 02 00 00 00 if w3 == 2 goto +1 <LBB0_66>
     138:       05 00 0a 00 00 00 00 00 goto +10 <LBB0_69>

0000000000000458 <LBB0_66>:
     139:       69 21 00 00 00 00 00 00 r1 = *(u16 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     140:       05 00 08 00 00 00 00 00 goto +8 <LBB0_69>

0000000000000468 <LBB0_63>:
     141:       16 03 06 00 04 00 00 00 if w3 == 4 goto +6 <LBB0_67>
     142:       16 03 01 00 08 00 00 00 if w3 == 8 goto +1 <LBB0_68>
     143:       05 00 05 00 00 00 00 00 goto +5 <LBB0_69>

0000000000000480 <LBB0_68>:
     144:       79 21 00 00 00 00 00 00 r1 = *(u64 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     145:       05 00 03 00 00 00 00 00 goto +3 <LBB0_69>

0000000000000490 <LBB0_65>:
     146:       71 21 00 00 00 00 00 00 r1 = *(u8 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^
     147:       05 00 01 00 00 00 00 00 goto +1 <LBB0_69>

00000000000004a0 <LBB0_67>:
     148:       61 21 00 00 00 00 00 00 r1 = *(u32 *)(r2 + 0)
; NO CO-RE relocation here                   ^^^^^^^^^^^^^^^^

00000000000004a8 <LBB0_69>:
     149:       67 01 00 00 20 00 00 00 r1 <<= 32
     150:       b7 02 00 00 00 00 00 00 r2 = 0
     151:       16 02 02 00 00 00 00 00 if w2 == 0 goto +2 <LBB0_71>
     152:       c7 01 00 00 20 00 00 00 r1 s>>= 32
     153:       05 00 01 00 00 00 00 00 goto +1 <LBB0_72>

00000000000004d0 <LBB0_71>:
     154:       77 01 00 00 20 00 00 00 r1 >>= 323

Fixes: ee26dad ("libbpf: Add support for relocatable bitfields")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/20210426192949.416837-4-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue May 22, 2021
[ Upstream commit d5027ca ]

Ritesh reported a bug [1] against UML, noting that it crashed on
startup. The backtrace shows the following (heavily redacted):

(gdb) bt
...
 linux-sunxi#26 0x0000000060015b5d in sem_init () at ipc/sem.c:268
 linux-sunxi#27 0x00007f89906d92f7 in ?? () from /lib/x86_64-linux-gnu/libcom_err.so.2
 linux-sunxi#28 0x00007f8990ab8fb2 in call_init (...) at dl-init.c:72
...
 linux-sunxi#40 0x00007f89909bf3a6 in nss_load_library (...) at nsswitch.c:359
...
 linux-sunxi#44 0x00007f8990895e35 in _nss_compat_getgrnam_r (...) at nss_compat/compat-grp.c:486
 linux-sunxi#45 0x00007f8990968b85 in __getgrnam_r [...]
 linux-sunxi#46 0x00007f89909d6b77 in grantpt [...]
 linux-sunxi#47 0x00007f8990a9394e in __GI_openpty [...]
 linux-sunxi#48 0x00000000604a1f65 in openpty_cb (...) at arch/um/os-Linux/sigio.c:407
 linux-sunxi#49 0x00000000604a58d0 in start_idle_thread (...) at arch/um/os-Linux/skas/process.c:598
 linux-sunxi#50 0x0000000060004a3d in start_uml () at arch/um/kernel/skas/process.c:45
 linux-sunxi#51 0x00000000600047b2 in linux_main (...) at arch/um/kernel/um_arch.c:334
 linux-sunxi#52 0x000000006000574f in main (...) at arch/um/os-Linux/main.c:144

indicating that the UML function openpty_cb() calls openpty(),
which internally calls __getgrnam_r(), which causes the nsswitch
machinery to get started.

This loads, through lots of indirection that I snipped, the
libcom_err.so.2 library, which (in an unknown function, "??")
calls sem_init().

Now, of course it wants to get libpthread's sem_init(), since
it's linked against libpthread. However, the dynamic linker
looks up that symbol against the binary first, and gets the
kernel's sem_init().

Hajime Tazaki noted that "objcopy -L" can localize a symbol,
so the dynamic linker wouldn't do the lookup this way. I tried,
but for some reason that didn't seem to work.

Doing the same thing in the linker script instead does seem to
work, though I cannot entirely explain - it *also* works if I
just add "VERSION { { global: *; }; }" instead, indicating that
something else is happening that I don't really understand. It
may be that explicitly doing that marks them with some kind of
empty version, and that's different from the default.

Explicitly marking them with a version breaks kallsyms, so that
doesn't seem to be possible.

Marking all the symbols as local seems correct, and does seem
to address the issue, so do that. Also do it for static link,
nsswitch libraries could still be loaded there.

[1] https://bugs.debian.org/983379

Reported-by: Ritesh Raj Sarraf <rrs@debian.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Tested-By: Ritesh Raj Sarraf <rrs@debian.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue May 24, 2021
[ Upstream commit d5027ca ]

Ritesh reported a bug [1] against UML, noting that it crashed on
startup. The backtrace shows the following (heavily redacted):

(gdb) bt
...
 linux-sunxi#26 0x0000000060015b5d in sem_init () at ipc/sem.c:268
 linux-sunxi#27 0x00007f89906d92f7 in ?? () from /lib/x86_64-linux-gnu/libcom_err.so.2
 linux-sunxi#28 0x00007f8990ab8fb2 in call_init (...) at dl-init.c:72
...
 linux-sunxi#40 0x00007f89909bf3a6 in nss_load_library (...) at nsswitch.c:359
...
 linux-sunxi#44 0x00007f8990895e35 in _nss_compat_getgrnam_r (...) at nss_compat/compat-grp.c:486
 linux-sunxi#45 0x00007f8990968b85 in __getgrnam_r [...]
 linux-sunxi#46 0x00007f89909d6b77 in grantpt [...]
 linux-sunxi#47 0x00007f8990a9394e in __GI_openpty [...]
 linux-sunxi#48 0x00000000604a1f65 in openpty_cb (...) at arch/um/os-Linux/sigio.c:407
 linux-sunxi#49 0x00000000604a58d0 in start_idle_thread (...) at arch/um/os-Linux/skas/process.c:598
 linux-sunxi#50 0x0000000060004a3d in start_uml () at arch/um/kernel/skas/process.c:45
 linux-sunxi#51 0x00000000600047b2 in linux_main (...) at arch/um/kernel/um_arch.c:334
 linux-sunxi#52 0x000000006000574f in main (...) at arch/um/os-Linux/main.c:144

indicating that the UML function openpty_cb() calls openpty(),
which internally calls __getgrnam_r(), which causes the nsswitch
machinery to get started.

This loads, through lots of indirection that I snipped, the
libcom_err.so.2 library, which (in an unknown function, "??")
calls sem_init().

Now, of course it wants to get libpthread's sem_init(), since
it's linked against libpthread. However, the dynamic linker
looks up that symbol against the binary first, and gets the
kernel's sem_init().

Hajime Tazaki noted that "objcopy -L" can localize a symbol,
so the dynamic linker wouldn't do the lookup this way. I tried,
but for some reason that didn't seem to work.

Doing the same thing in the linker script instead does seem to
work, though I cannot entirely explain - it *also* works if I
just add "VERSION { { global: *; }; }" instead, indicating that
something else is happening that I don't really understand. It
may be that explicitly doing that marks them with some kind of
empty version, and that's different from the default.

Explicitly marking them with a version breaks kallsyms, so that
doesn't seem to be possible.

Marking all the symbols as local seems correct, and does seem
to address the issue, so do that. Also do it for static link,
nsswitch libraries could still be loaded there.

[1] https://bugs.debian.org/983379

Reported-by: Ritesh Raj Sarraf <rrs@debian.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Tested-By: Ritesh Raj Sarraf <rrs@debian.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Jun 23, 2021
nft_set_elem_expr_alloc() needs an initialized set if expression sets on
the NFT_EXPR_GC flag. Move set fields initialization before expression
setup.

[4512935.019450] ==================================================================
[4512935.019456] BUG: KASAN: null-ptr-deref in nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019487] Read of size 8 at addr 0000000000000070 by task nft/23532
[4512935.019494] CPU: 1 PID: 23532 Comm: nft Not tainted 5.12.0-rc4+ linux-sunxi#48
[...]
[4512935.019502] Call Trace:
[4512935.019505]  dump_stack+0x89/0xb4
[4512935.019512]  ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019536]  ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019560]  kasan_report.cold.12+0x5f/0xd8
[4512935.019566]  ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019590]  nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019615]  nf_tables_newset+0xc7f/0x1460 [nf_tables]

Reported-by: syzbot+ce96ca2b1d0b37c6422d@syzkaller.appspotmail.com
Fixes: 6503842 ("netfilter: nf_tables: allow to specify stateful expression in set definition")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Jul 20, 2021
[ Upstream commit ad9f151 ]

nft_set_elem_expr_alloc() needs an initialized set if expression sets on
the NFT_EXPR_GC flag. Move set fields initialization before expression
setup.

[4512935.019450] ==================================================================
[4512935.019456] BUG: KASAN: null-ptr-deref in nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019487] Read of size 8 at addr 0000000000000070 by task nft/23532
[4512935.019494] CPU: 1 PID: 23532 Comm: nft Not tainted 5.12.0-rc4+ linux-sunxi#48
[...]
[4512935.019502] Call Trace:
[4512935.019505]  dump_stack+0x89/0xb4
[4512935.019512]  ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019536]  ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019560]  kasan_report.cold.12+0x5f/0xd8
[4512935.019566]  ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019590]  nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019615]  nf_tables_newset+0xc7f/0x1460 [nf_tables]

Reported-by: syzbot+ce96ca2b1d0b37c6422d@syzkaller.appspotmail.com
Fixes: 6503842 ("netfilter: nf_tables: allow to specify stateful expression in set definition")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Sep 17, 2021
commit ad9f151 upstream.

nft_set_elem_expr_alloc() needs an initialized set if expression sets on
the NFT_EXPR_GC flag. Move set fields initialization before expression
setup.

[4512935.019450] ==================================================================
[4512935.019456] BUG: KASAN: null-ptr-deref in nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019487] Read of size 8 at addr 0000000000000070 by task nft/23532
[4512935.019494] CPU: 1 PID: 23532 Comm: nft Not tainted 5.12.0-rc4+ linux-sunxi#48
[...]
[4512935.019502] Call Trace:
[4512935.019505]  dump_stack+0x89/0xb4
[4512935.019512]  ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019536]  ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019560]  kasan_report.cold.12+0x5f/0xd8
[4512935.019566]  ? nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019590]  nft_set_elem_expr_alloc+0x84/0xd0 [nf_tables]
[4512935.019615]  nf_tables_newset+0xc7f/0x1460 [nf_tables]

Reported-by: syzbot+ce96ca2b1d0b37c6422d@syzkaller.appspotmail.com
Fixes: 6503842 ("netfilter: nf_tables: allow to specify stateful expression in set definition")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
repojohnray pushed a commit to repojohnray/linux-sunxi-4.7.y that referenced this issue Dec 13, 2023
[ Upstream commit fe57575 ]

The `cgrp_local_storage` test triggers a kernel panic like:

  # ./test_progs -t cgrp_local_storage
  Can't find bpf_testmod.ko kernel module: -2
  WARNING! Selftests relying on bpf_testmod.ko will be skipped.
  [  550.930632] CPU 1 Unable to handle kernel paging request at virtual address 0000000000000080, era == ffff80000200be34, ra == ffff80000200be00
  [  550.931781] Oops[jwrdegoede#1]:
  [  550.931966] CPU: 1 PID: 1303 Comm: test_progs Not tainted 6.7.0-rc2-loong-devel-g2f56bb0d2327 linux-sunxi#35 a896aca3f4164f09cc346f89f2e09832e07be5f6
  [  550.932215] Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022
  [  550.932403] pc ffff80000200be34 ra ffff80000200be00 tp 9000000108350000 sp 9000000108353dc0
  [  550.932545] a0 0000000000000000 a1 0000000000000517 a2 0000000000000118 a3 00007ffffbb15558
  [  550.932682] a4 00007ffffbb15620 a5 90000001004e7700 a6 0000000000000021 a7 0000000000000118
  [  550.932824] t0 ffff80000200bdc0 t1 0000000000000517 t2 0000000000000517 t3 00007ffff1c06ee0
  [  550.932961] t4 0000555578ae04d0 t5 fffffffffffffff8 t6 0000000000000004 t7 0000000000000020
  [  550.933097] t8 0000000000000040 u0 00000000000007b8 s9 9000000108353e00 s0 90000001004e7700
  [  550.933241] s1 9000000004005000 s2 0000000000000001 s3 0000000000000000 s4 0000555555eb2ec8
  [  550.933379] s5 00007ffffbb15bb8 s6 00007ffff1dafd60 s7 000055555663f610 s8 00007ffff1db0050
  [  550.933520]    ra: ffff80000200be00 bpf_prog_98f1b9e767be2a84_on_enter+0x40/0x200
  [  550.933911]   ERA: ffff80000200be34 bpf_prog_98f1b9e767be2a84_on_enter+0x74/0x200
  [  550.934105]  CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
  [  550.934596]  PRMD: 00000004 (PPLV0 +PIE -PWE)
  [  550.934712]  EUEN: 00000003 (+FPE +SXE -ASXE -BTE)
  [  550.934836]  ECFG: 00071c1c (LIE=2-4,10-12 VS=7)
  [  550.934976] ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
  [  550.935097]  BADV: 0000000000000080
  [  550.935181]  PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
  [  550.935291] Modules linked in:
  [  550.935391] Process test_progs (pid: 1303, threadinfo=000000006c3b1c41, task=0000000061f84a55)
  [  550.935643] Stack : 00007ffffbb15bb8 0000555555eb2ec8 0000000000000000 0000000000000001
  [  550.935844]         9000000004005000 ffff80001b864000 00007ffffbb15450 90000000029aa034
  [  550.935990]         0000000000000000 9000000108353ec0 0000000000000118 d07d9dfb09721a09
  [  550.936175]         0000000000000001 0000000000000000 9000000108353ec0 0000000000000118
  [  550.936314]         9000000101d46ad0 900000000290abf0 000055555663f610 0000000000000000
  [  550.936479]         0000000000000003 9000000108353ec0 00007ffffbb15450 90000000029d7288
  [  550.936635]         00007ffff1dafd60 000055555663f610 0000000000000000 0000000000000003
  [  550.936779]         9000000108353ec0 90000000035dd1f0 00007ffff1dafd58 9000000002841c5c
  [  550.936939]         0000000000000119 0000555555eea5a8 00007ffff1d78780 00007ffffbb153e0
  [  550.937083]         ffffffffffffffda 00007ffffbb15518 0000000000000040 00007ffffbb15558
  [  550.937224]         ...
  [  550.937299] Call Trace:
  [  550.937521] [<ffff80000200be34>] bpf_prog_98f1b9e767be2a84_on_enter+0x74/0x200
  [  550.937910] [<90000000029aa034>] bpf_trace_run2+0x90/0x154
  [  550.938105] [<900000000290abf0>] syscall_trace_enter.isra.0+0x1cc/0x200
  [  550.938224] [<90000000035dd1f0>] do_syscall+0x48/0x94
  [  550.938319] [<9000000002841c5c>] handle_syscall+0xbc/0x158
  [  550.938477]
  [  550.938607] Code: 580009ae  50016000  262402e4 <28c20085> 14092084  03a00084  16000024  03240084  00150006
  [  550.938851]
  [  550.939021] ---[ end trace 0000000000000000 ]---

Further investigation shows that this panic is triggered by memory
load operations:

  ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0,
                             BPF_LOCAL_STORAGE_GET_F_CREATE);

The expression `task->cgroups->dfl_cgrp` involves two memory load.
Since the field offset fits in imm12 or imm14, we use ldd or ldptrd
instructions. But both instructions have the side effect that it will
signed-extended the imm operand. Finally, we got the wrong addresses
and panics is inevitable.

Use a generic ldxd instruction to avoid this kind of issues.

With this change, we have:

  # ./test_progs -t cgrp_local_storage
  Can't find bpf_testmod.ko kernel module: -2
  WARNING! Selftests relying on bpf_testmod.ko will be skipped.
  test_cgrp_local_storage:PASS:join_cgroup /cgrp_local_storage 0 nsec
  linux-sunxi#48/1    cgrp_local_storage/tp_btf:OK
  test_attach_cgroup:PASS:skel_open 0 nsec
  test_attach_cgroup:PASS:prog_attach 0 nsec
  test_attach_cgroup:PASS:prog_attach 0 nsec
  libbpf: prog 'update_cookie_tracing': failed to attach: ERROR: strerror_r(-524)=22
  test_attach_cgroup:FAIL:prog_attach unexpected error: -524
  linux-sunxi#48/2    cgrp_local_storage/attach_cgroup:FAIL
  test_recursion:PASS:skel_open_and_load 0 nsec
  libbpf: prog 'on_lookup': failed to attach: ERROR: strerror_r(-524)=22
  libbpf: prog 'on_lookup': failed to auto-attach: -524
  test_recursion:FAIL:skel_attach unexpected error: -524 (errno 524)
  linux-sunxi#48/3    cgrp_local_storage/recursion:FAIL
  linux-sunxi#48/4    cgrp_local_storage/negative:OK
  linux-sunxi#48/5    cgrp_local_storage/cgroup_iter_sleepable:OK
  test_yes_rcu_lock:PASS:skel_open 0 nsec
  test_yes_rcu_lock:PASS:skel_load 0 nsec
  libbpf: prog 'yes_rcu_lock': failed to attach: ERROR: strerror_r(-524)=22
  libbpf: prog 'yes_rcu_lock': failed to auto-attach: -524
  test_yes_rcu_lock:FAIL:skel_attach unexpected error: -524 (errno 524)
  linux-sunxi#48/6    cgrp_local_storage/yes_rcu_lock:FAIL
  linux-sunxi#48/7    cgrp_local_storage/no_rcu_lock:OK
  linux-sunxi#48      cgrp_local_storage:FAIL

  All error logs:
  test_cgrp_local_storage:PASS:join_cgroup /cgrp_local_storage 0 nsec
  test_attach_cgroup:PASS:skel_open 0 nsec
  test_attach_cgroup:PASS:prog_attach 0 nsec
  test_attach_cgroup:PASS:prog_attach 0 nsec
  libbpf: prog 'update_cookie_tracing': failed to attach: ERROR: strerror_r(-524)=22
  test_attach_cgroup:FAIL:prog_attach unexpected error: -524
  linux-sunxi#48/2    cgrp_local_storage/attach_cgroup:FAIL
  test_recursion:PASS:skel_open_and_load 0 nsec
  libbpf: prog 'on_lookup': failed to attach: ERROR: strerror_r(-524)=22
  libbpf: prog 'on_lookup': failed to auto-attach: -524
  test_recursion:FAIL:skel_attach unexpected error: -524 (errno 524)
  linux-sunxi#48/3    cgrp_local_storage/recursion:FAIL
  test_yes_rcu_lock:PASS:skel_open 0 nsec
  test_yes_rcu_lock:PASS:skel_load 0 nsec
  libbpf: prog 'yes_rcu_lock': failed to attach: ERROR: strerror_r(-524)=22
  libbpf: prog 'yes_rcu_lock': failed to auto-attach: -524
  test_yes_rcu_lock:FAIL:skel_attach unexpected error: -524 (errno 524)
  linux-sunxi#48/6    cgrp_local_storage/yes_rcu_lock:FAIL
  linux-sunxi#48      cgrp_local_storage:FAIL
  Summary: 0/4 PASSED, 0 SKIPPED, 1 FAILED

No panics any more (The test still failed because lack of BPF trampoline
which I am actively working on).

Fixes: 5dc6155 ("LoongArch: Add BPF JIT support")
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
jwrdegoede pushed a commit to jwrdegoede/linux-sunxi that referenced this issue Apr 30, 2024
Currently normal HugeTLB fault ends up crashing the kernel, as p4dp derived
from p4d_offset() is an invalid address when PGTABLE_LEVEL = 5. A p4d level
entry needs to be allocated when not available while walking the page table
during HugeTLB faults. Let's call p4d_alloc() to allocate such entries when
required instead of current p4d_offset().

 Unable to handle kernel paging request at virtual address ffffffff80000000
 Mem abort info:
   ESR = 0x0000000096000005
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
   FSC = 0x05: level 1 translation fault
 Data abort info:
   ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
 swapper pgtable: 4k pages, 52-bit VAs, pgdp=0000000081da9000
 [ffffffff80000000] pgd=1000000082cec003, p4d=0000000082c32003, pud=0000000000000000
 Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
 Modules linked in:
 CPU: 1 PID: 108 Comm: high_addr_hugep Not tainted 6.9.0-rc4 linux-sunxi#48
 Hardware name: Foundation-v8A (DT)
 pstate: 01402005 (nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
 pc : huge_pte_alloc+0xd4/0x334
 lr : hugetlb_fault+0x1b8/0xc68
 sp : ffff8000833bbc20
 x29: ffff8000833bbc20 x28: fff000080080cb58 x27: ffff800082a7cc58
 x26: 0000000000000000 x25: fff0000800378e40 x24: fff00008008d6c60
 x23: 00000000de9dbf07 x22: fff0000800378e40 x21: 0004000000000000
 x20: 0004000000000000 x19: ffffffff80000000 x18: 1ffe00010011d7a1
 x17: 0000000000000001 x16: ffffffffffffffff x15: 0000000000000001
 x14: 0000000000000000 x13: ffff8000816120d0 x12: ffffffffffffffff
 x11: 0000000000000000 x10: fff00008008ebd0c x9 : 0004000000000000
 x8 : 0000000000001255 x7 : fff00008003e2000 x6 : 00000000061d54b0
 x5 : 0000000000001000 x4 : ffffffff80000000 x3 : 0000000000200000
 x2 : 0000000000000004 x1 : 0000000080000000 x0 : 0000000000000000
 Call trace:
 huge_pte_alloc+0xd4/0x334
 hugetlb_fault+0x1b8/0xc68
 handle_mm_fault+0x260/0x29c
 do_page_fault+0xfc/0x47c
 do_translation_fault+0x68/0x74
 do_mem_abort+0x44/0x94
 el0_da+0x2c/0x9c
 el0t_64_sync_handler+0x70/0xc4
 el0t_64_sync+0x190/0x194
 Code: aa000084 cb010084 b24c2c84 8b130c93 (f9400260)
 ---[ end trace 0000000000000000 ]---

Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Fixes: a6bbf5d ("arm64: mm: Add definitions to support 5 levels of paging")
Reported-by: Dev Jain <dev.jain@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Link: https://lore.kernel.org/r/20240415094003.1812018-1-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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