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Debug/makefile #35

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merged 2 commits into from
Jul 17, 2018
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removed unused Kconfig/Makefile options and don't build SOF with module (m) as default

This option points to non-existent files, remove.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Not sure why this was added but this is not quite right

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
@plbossart plbossart requested a review from lgirdwood July 16, 2018 18:47
@plbossart plbossart merged commit 26c56d7 into thesofproject:topic/sof-dev Jul 17, 2018
cujomalainey pushed a commit to cujomalainey/linux that referenced this pull request Jan 30, 2019
[ Upstream commit 81e9fa8 ]

The armv8_pmuv3 driver doesn't have a remove function, and when the test
'CONFIG_DEBUG_TEST_DRIVER_REMOVE=y' is enabled, the following Call trace
can be seen.

[    1.424287] Failed to register pmu: armv8_pmuv3, reason -17
[    1.424870] WARNING: CPU: 0 PID: 1 at ../kernel/events/core.c:11771 perf_event_sysfs_init+0x98/0xdc
[    1.425220] Modules linked in:
[    1.425531] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W         4.19.0-rc7-next-20181012-00003-ge7a97b1ad77b-dirty thesofproject#35
[    1.425951] Hardware name: linux,dummy-virt (DT)
[    1.426212] pstate: 80000005 (Nzcv daif -PAN -UAO)
[    1.426458] pc : perf_event_sysfs_init+0x98/0xdc
[    1.426720] lr : perf_event_sysfs_init+0x98/0xdc
[    1.426908] sp : ffff00000804bd50
[    1.427077] x29: ffff00000804bd50 x28: ffff00000934e078
[    1.427429] x27: ffff000009546000 x26: 0000000000000007
[    1.427757] x25: ffff000009280710 x24: 00000000ffffffef
[    1.428086] x23: ffff000009408000 x22: 0000000000000000
[    1.428415] x21: ffff000009136008 x20: ffff000009408730
[    1.428744] x19: ffff80007b20b400 x18: 000000000000000a
[    1.429075] x17: 0000000000000000 x16: 0000000000000000
[    1.429418] x15: 0000000000000400 x14: 2e79726f74636572
[    1.429748] x13: 696420656d617320 x12: 656874206e692065
[    1.430060] x11: 6d616e20656d6173 x10: 2065687420687469
[    1.430335] x9 : ffff00000804bd50 x8 : 206e6f7361657220
[    1.430610] x7 : 2c3376756d705f38 x6 : ffff00000954d7ce
[    1.430880] x5 : 0000000000000000 x4 : 0000000000000000
[    1.431226] x3 : 0000000000000000 x2 : ffffffffffffffff
[    1.431554] x1 : 4d151327adc50b00 x0 : 0000000000000000
[    1.431868] Call trace:
[    1.432102]  perf_event_sysfs_init+0x98/0xdc
[    1.432382]  do_one_initcall+0x6c/0x1a8
[    1.432637]  kernel_init_freeable+0x1bc/0x280
[    1.432905]  kernel_init+0x18/0x160
[    1.433115]  ret_from_fork+0x10/0x18
[    1.433297] ---[ end trace 27fd415390eb9883 ]---

Rework to set suppress_bind_attrs flag to avoid removing the device when
CONFIG_DEBUG_TEST_DRIVER_REMOVE=y, since there's no real reason to
remove the armv8_pmuv3 driver.

Cc: Arnd Bergmann <arnd@arndb.de>
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
plbossart pushed a commit that referenced this pull request Feb 13, 2020
Because 'q->flags' starts as zero, and zero is a valid value, we
aren't able to detect the transition from zero to something else
during "runtime".

The solution is to initialize 'q->flags' with an invalid value, so we
can detect if 'q->flags' was set by the user or not.

To better solidify the behavior, 'flags' handling is moved to a
separate function. The behavior is:
 - 'flags' if unspecified by the user, is assumed to be zero;
 - 'flags' cannot change during "runtime" (i.e. a change() request
 cannot modify it);

With this new function we can remove taprio_flags, which should reduce
the risk of future accidents.

Allowing flags to be changed was causing the following RCU stall:

[ 1730.558249] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
[ 1730.558258] rcu: 	  6-...0: (190 ticks this GP) idle=922/0/0x1 softirq=25580/25582 fqs=16250
[ 1730.558264] 		  (detected by 2, t=65002 jiffies, g=33017, q=81)
[ 1730.558269] Sending NMI from CPU 2 to CPUs 6:
[ 1730.559277] NMI backtrace for cpu 6
[ 1730.559277] CPU: 6 PID: 0 Comm: swapper/6 Tainted: G            E     5.5.0-rc6+ #35
[ 1730.559278] Hardware name: Gigabyte Technology Co., Ltd. Z390 AORUS ULTRA/Z390 AORUS ULTRA-CF, BIOS F7 03/14/2019
[ 1730.559278] RIP: 0010:__hrtimer_run_queues+0xe2/0x440
[ 1730.559278] Code: 48 8b 43 28 4c 89 ff 48 8b 75 c0 48 89 45 c8 e8 f4 bb 7c 00 0f 1f 44 00 00 65 8b 05 40 31 f0 68 89 c0 48 0f a3 05 3e 5c 25 01 <0f> 82 fc 01 00 00 48 8b 45 c8 48 89 df ff d0 89 45 c8 0f 1f 44 00
[ 1730.559279] RSP: 0018:ffff9970802d8f10 EFLAGS: 00000083
[ 1730.559279] RAX: 0000000000000006 RBX: ffff8b31645bff38 RCX: 0000000000000000
[ 1730.559280] RDX: 0000000000000000 RSI: ffffffff9710f2ec RDI: ffffffff978daf0e
[ 1730.559280] RBP: ffff9970802d8f68 R08: 0000000000000000 R09: 0000000000000000
[ 1730.559280] R10: 0000018336d7944e R11: 0000000000000001 R12: ffff8b316e39f9c0
[ 1730.559281] R13: ffff8b316e39f940 R14: ffff8b316e39f998 R15: ffff8b316e39f7c0
[ 1730.559281] FS:  0000000000000000(0000) GS:ffff8b316e380000(0000) knlGS:0000000000000000
[ 1730.559281] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1730.559281] CR2: 00007f1105303760 CR3: 0000000227210005 CR4: 00000000003606e0
[ 1730.559282] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1730.559282] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1730.559282] Call Trace:
[ 1730.559282]  <IRQ>
[ 1730.559283]  ? taprio_dequeue_soft+0x2d0/0x2d0 [sch_taprio]
[ 1730.559283]  hrtimer_interrupt+0x104/0x220
[ 1730.559283]  ? irqtime_account_irq+0x34/0xa0
[ 1730.559283]  smp_apic_timer_interrupt+0x6d/0x230
[ 1730.559284]  apic_timer_interrupt+0xf/0x20
[ 1730.559284]  </IRQ>
[ 1730.559284] RIP: 0010:cpu_idle_poll+0x35/0x1a0
[ 1730.559285] Code: 88 82 ff 65 44 8b 25 12 7d 73 68 0f 1f 44 00 00 e8 90 c3 89 ff fb 65 48 8b 1c 25 c0 7e 01 00 48 8b 03 a8 08 74 0b eb 1c f3 90 <48> 8b 03 a8 08 75 13 8b 05 be a8 a8 00 85 c0 75 ed e8 75 48 84 ff
[ 1730.559285] RSP: 0018:ffff997080137ea8 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
[ 1730.559285] RAX: 0000000000000001 RBX: ffff8b316bc3c580 RCX: 0000000000000000
[ 1730.559286] RDX: 0000000000000001 RSI: 000000002819aad9 RDI: ffffffff978da730
[ 1730.559286] RBP: ffff997080137ec0 R08: 0000018324a6d387 R09: 0000000000000000
[ 1730.559286] R10: 0000000000000400 R11: 0000000000000001 R12: 0000000000000006
[ 1730.559286] R13: ffff8b316bc3c580 R14: 0000000000000000 R15: 0000000000000000
[ 1730.559287]  ? cpu_idle_poll+0x20/0x1a0
[ 1730.559287]  ? cpu_idle_poll+0x20/0x1a0
[ 1730.559287]  do_idle+0x4d/0x1f0
[ 1730.559287]  ? complete+0x44/0x50
[ 1730.559288]  cpu_startup_entry+0x1b/0x20
[ 1730.559288]  start_secondary+0x142/0x180
[ 1730.559288]  secondary_startup_64+0xb6/0xc0
[ 1776.686313] nvme nvme0: I/O 96 QID 1 timeout, completion polled

Fixes: 4cfd577 ("taprio: Add support for txtime-assist mode")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bardliao pushed a commit to bardliao/linux that referenced this pull request Sep 4, 2020
In the existing NVMeOF Passthru core command handling on failure of
nvme_alloc_request() it errors out with rq value set to NULL. In the
error handling path it calls blk_put_request() without checking if
rq is set to NULL or not which produces following Oops:-

[ 1457.346861] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 1457.347838] #PF: supervisor read access in kernel mode
[ 1457.348464] #PF: error_code(0x0000) - not-present page
[ 1457.349085] PGD 0 P4D 0
[ 1457.349402] Oops: 0000 [#1] SMP NOPTI
[ 1457.349851] CPU: 18 PID: 10782 Comm: kworker/18:2 Tainted: G           OE     5.8.0-rc4nvme-5.9+ thesofproject#35
[ 1457.350951] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e3214
[ 1457.352347] Workqueue: events nvme_loop_execute_work [nvme_loop]
[ 1457.353062] RIP: 0010:blk_mq_free_request+0xe/0x110
[ 1457.353651] Code: 3f ff ff ff 83 f8 01 75 0d 4c 89 e7 e8 1b db ff ff e9 2d ff ff ff 0f 0b eb ef 66 8
[ 1457.355975] RSP: 0018:ffffc900035b7de0 EFLAGS: 00010282
[ 1457.356636] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002
[ 1457.357526] RDX: ffffffffa060bd05 RSI: 0000000000000000 RDI: 0000000000000000
[ 1457.358416] RBP: 0000000000000037 R08: 0000000000000000 R09: 0000000000000000
[ 1457.359317] R10: 0000000000000000 R11: 000000000000006d R12: 0000000000000000
[ 1457.360424] R13: ffff8887ffa68600 R14: 0000000000000000 R15: ffff8888150564c8
[ 1457.361322] FS:  0000000000000000(0000) GS:ffff888814600000(0000) knlGS:0000000000000000
[ 1457.362337] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1457.363058] CR2: 0000000000000000 CR3: 000000081c0ac000 CR4: 00000000003406e0
[ 1457.363973] Call Trace:
[ 1457.364296]  nvmet_passthru_execute_cmd+0x150/0x2c0 [nvmet]
[ 1457.364990]  process_one_work+0x24e/0x5a0
[ 1457.365493]  ? __schedule+0x353/0x840
[ 1457.365957]  worker_thread+0x3c/0x380
[ 1457.366426]  ? process_one_work+0x5a0/0x5a0
[ 1457.366948]  kthread+0x135/0x150
[ 1457.367362]  ? kthread_create_on_node+0x60/0x60
[ 1457.367934]  ret_from_fork+0x22/0x30
[ 1457.368388] Modules linked in: nvme_loop(OE) nvmet(OE) nvme_fabrics(OE) null_blk nvme(OE) nvme_corer
[ 1457.368414]  ata_piix crc32c_intel virtio_pci libata virtio_ring serio_raw t10_pi virtio floppy dm_]
[ 1457.380849] CR2: 0000000000000000
[ 1457.381288] ---[ end trace c6cab61bfd1f68fd ]---
[ 1457.381861] RIP: 0010:blk_mq_free_request+0xe/0x110
[ 1457.382469] Code: 3f ff ff ff 83 f8 01 75 0d 4c 89 e7 e8 1b db ff ff e9 2d ff ff ff 0f 0b eb ef 66 8
[ 1457.384749] RSP: 0018:ffffc900035b7de0 EFLAGS: 00010282
[ 1457.385393] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002
[ 1457.386264] RDX: ffffffffa060bd05 RSI: 0000000000000000 RDI: 0000000000000000
[ 1457.387142] RBP: 0000000000000037 R08: 0000000000000000 R09: 0000000000000000
[ 1457.388029] R10: 0000000000000000 R11: 000000000000006d R12: 0000000000000000
[ 1457.388914] R13: ffff8887ffa68600 R14: 0000000000000000 R15: ffff8888150564c8
[ 1457.389798] FS:  0000000000000000(0000) GS:ffff888814600000(0000) knlGS:0000000000000000
[ 1457.390796] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1457.391508] CR2: 0000000000000000 CR3: 000000081c0ac000 CR4: 00000000003406e0
[ 1457.392525] Kernel panic - not syncing: Fatal exception
[ 1457.394138] Kernel Offset: disabled
[ 1457.394677] ---[ end Kernel panic - not syncing: Fatal exception ]---

We fix this Oops by adding a new goto label out_put_req and reordering
the blk_put_request call to avoid calling blk_put_request() with rq
value is set to NULL. Here we also update the rest of the code
accordingly.

Fixes: 06b7164dfdc0 ("nvmet: add passthru code to process commands")
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
plbossart pushed a commit that referenced this pull request Sep 28, 2020
Get and put the reference to the ctrl in the nvme_dev_open() and
nvme_dev_release() before and after module get/put for ctrl in char
device file operations.

Introduce char_dev relase function, get/put the controller and module
which allows us to fix the potential Oops which can be easily reproduced
with a passthru ctrl (although the problem also exists with pure user
access):

Entering kdb (current=0xffff8887f8290000, pid 3128) on processor 30 Oops: (null)
due to oops @ 0xffffffffa01019ad
CPU: 30 PID: 3128 Comm: bash Tainted: G        W  OE     5.8.0-rc4nvme-5.9+ #35
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.4
RIP: 0010:nvme_free_ctrl+0x234/0x285 [nvme_core]
Code: 57 10 a0 e8 73 bf 02 e1 ba 3d 11 00 00 48 c7 c6 98 33 10 a0 48 c7 c7 1d 57 10 a0 e8 5b bf 02 e1 8
RSP: 0018:ffffc90001d63de0 EFLAGS: 00010246
RAX: ffffffffa05c0440 RBX: ffff8888119e45a0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8888177e9550 RDI: ffff8888119e43b0
RBP: ffff8887d4768000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffc90001d63c90 R12: ffff8888119e43b0
R13: ffff8888119e5108 R14: dead000000000100 R15: ffff8888119e5108
FS:  00007f1ef27b0740(0000) GS:ffff888817600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffa05c0470 CR3: 00000007f6bee000 CR4: 00000000003406e0
Call Trace:
 device_release+0x27/0x80
 kobject_put+0x98/0x170
 nvmet_passthru_ctrl_disable+0x4a/0x70 [nvmet]
 nvmet_passthru_enable_store+0x4c/0x90 [nvmet]
 configfs_write_file+0xe6/0x150
 vfs_write+0xba/0x1e0
 ksys_write+0x5f/0xe0
 do_syscall_64+0x52/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f1ef1eb2840
Code: Bad RIP value.
RSP: 002b:00007fffdbff0eb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f1ef1eb2840
RDX: 0000000000000002 RSI: 00007f1ef27d2000 RDI: 0000000000000001
RBP: 00007f1ef27d2000 R08: 000000000000000a R09: 00007f1ef27b0740
R10: 0000000000000001 R11: 0000000000000246 R12: 00007f1ef2186400
R13: 0000000000000002 R14: 0000000000000001 R15: 0000000000000000

With this patch fix we take the module ref count in nvme_dev_open() and
release that ref count in newly introduced nvme_dev_release().

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
cujomalainey pushed a commit to cujomalainey/linux that referenced this pull request Oct 26, 2020
[ Upstream commit 96298f6 ]

According to Core Spec Version 5.2 | Vol 3, Part A 6.1.5,
the incoming L2CAP_ConfigReq should be handled during
OPEN state.

The section below shows the btmon trace when running
L2CAP/COS/CFD/BV-12-C before and after this change.

=== Before ===
...
> ACL Data RX: Handle 256 flags 0x02 dlen 12                thesofproject#22
      L2CAP: Connection Request (0x02) ident 2 len 4
        PSM: 1 (0x0001)
        Source CID: 65
< ACL Data TX: Handle 256 flags 0x00 dlen 16                thesofproject#23
      L2CAP: Connection Response (0x03) ident 2 len 8
        Destination CID: 64
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 256 flags 0x00 dlen 12                thesofproject#24
      L2CAP: Configure Request (0x04) ident 2 len 4
        Destination CID: 65
        Flags: 0x0000
> HCI Event: Number of Completed Packets (0x13) plen 5      thesofproject#25
        Num handles: 1
        Handle: 256
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5      thesofproject#26
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 16                thesofproject#27
      L2CAP: Configure Request (0x04) ident 3 len 8
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00                                            ..
< ACL Data TX: Handle 256 flags 0x00 dlen 18                thesofproject#28
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 672
> HCI Event: Number of Completed Packets (0x13) plen 5      thesofproject#29
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 14                thesofproject#30
      L2CAP: Configure Response (0x05) ident 2 len 6
        Source CID: 64
        Flags: 0x0000
        Result: Success (0x0000)
> ACL Data RX: Handle 256 flags 0x02 dlen 20                thesofproject#31
      L2CAP: Configure Request (0x04) ident 3 len 12
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00 91 02 11 11                                ......
< ACL Data TX: Handle 256 flags 0x00 dlen 14                thesofproject#32
      L2CAP: Command Reject (0x01) ident 3 len 6
        Reason: Invalid CID in request (0x0002)
        Destination CID: 64
        Source CID: 65
> HCI Event: Number of Completed Packets (0x13) plen 5      thesofproject#33
        Num handles: 1
        Handle: 256
        Count: 1
...
=== After ===
...
> ACL Data RX: Handle 256 flags 0x02 dlen 12               thesofproject#22
      L2CAP: Connection Request (0x02) ident 2 len 4
        PSM: 1 (0x0001)
        Source CID: 65
< ACL Data TX: Handle 256 flags 0x00 dlen 16               thesofproject#23
      L2CAP: Connection Response (0x03) ident 2 len 8
        Destination CID: 64
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 256 flags 0x00 dlen 12               thesofproject#24
      L2CAP: Configure Request (0x04) ident 2 len 4
        Destination CID: 65
        Flags: 0x0000
> HCI Event: Number of Completed Packets (0x13) plen 5     thesofproject#25
        Num handles: 1
        Handle: 256
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5     thesofproject#26
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 16               thesofproject#27
      L2CAP: Configure Request (0x04) ident 3 len 8
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00                                            ..
< ACL Data TX: Handle 256 flags 0x00 dlen 18               thesofproject#28
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 672
> HCI Event: Number of Completed Packets (0x13) plen 5     thesofproject#29
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 14               thesofproject#30
      L2CAP: Configure Response (0x05) ident 2 len 6
        Source CID: 64
        Flags: 0x0000
        Result: Success (0x0000)
> ACL Data RX: Handle 256 flags 0x02 dlen 20               thesofproject#31
      L2CAP: Configure Request (0x04) ident 3 len 12
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00 91 02 11 11                                .....
< ACL Data TX: Handle 256 flags 0x00 dlen 18               thesofproject#32
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 672
< ACL Data TX: Handle 256 flags 0x00 dlen 12               thesofproject#33
      L2CAP: Configure Request (0x04) ident 3 len 4
        Destination CID: 65
        Flags: 0x0000
> HCI Event: Number of Completed Packets (0x13) plen 5     thesofproject#34
        Num handles: 1
        Handle: 256
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5     thesofproject#35
        Num handles: 1
        Handle: 256
        Count: 1
...

Signed-off-by: Howard Chung <howardchung@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
plbossart pushed a commit that referenced this pull request Mar 4, 2021
Brian Foster reported a lockdep warning on xfs/167:

============================================
WARNING: possible recursive locking detected
5.11.0-rc4 #35 Tainted: G        W I
--------------------------------------------
fsstress/17733 is trying to acquire lock:
ffff8e0fd1d90650 (sb_internal){++++}-{0:0}, at: xfs_free_eofblocks+0x104/0x1d0 [xfs]

but task is already holding lock:
ffff8e0fd1d90650 (sb_internal){++++}-{0:0}, at: xfs_trans_alloc_inode+0x5f/0x160 [xfs]

stack backtrace:
CPU: 38 PID: 17733 Comm: fsstress Tainted: G        W I       5.11.0-rc4 #35
Hardware name: Dell Inc. PowerEdge R740/01KPX8, BIOS 1.6.11 11/20/2018
Call Trace:
 dump_stack+0x8b/0xb0
 __lock_acquire.cold+0x159/0x2ab
 lock_acquire+0x116/0x370
 xfs_trans_alloc+0x1ad/0x310 [xfs]
 xfs_free_eofblocks+0x104/0x1d0 [xfs]
 xfs_blockgc_scan_inode+0x24/0x60 [xfs]
 xfs_inode_walk_ag+0x202/0x4b0 [xfs]
 xfs_inode_walk+0x66/0xc0 [xfs]
 xfs_trans_alloc+0x160/0x310 [xfs]
 xfs_trans_alloc_inode+0x5f/0x160 [xfs]
 xfs_alloc_file_space+0x105/0x300 [xfs]
 xfs_file_fallocate+0x270/0x460 [xfs]
 vfs_fallocate+0x14d/0x3d0
 __x64_sys_fallocate+0x3e/0x70
 do_syscall_64+0x33/0x40
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The cause of this is the new code that spurs a scan to garbage collect
speculative preallocations if we fail to reserve enough blocks while
allocating a transaction.  While the warning itself is a fairly benign
lockdep complaint, it does expose a potential livelock if the rwsem
behavior ever changes with regards to nesting read locks when someone's
waiting for a write lock.

Fix this by freeing the transaction and jumping back to xfs_trans_alloc
like this patch in the V4 submission[1].

[1] https://lore.kernel.org/linux-xfs/161142798066.2171939.9311024588681972086.stgit@magnolia/

Fixes: a1a7d05 ("xfs: flush speculative space allocations when we run out of space")
Reported-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
aiChaoSONG pushed a commit to aiChaoSONG/linux that referenced this pull request May 6, 2021
crojewsk-intel pushed a commit to crojewsk-intel/linux that referenced this pull request Nov 2, 2022
Inspired by commit 9fb7410("arm64/BUG: Use BRK instruction for
generic BUG traps"), do similar for LoongArch to use generic BUG()
handler.

This patch uses the BREAK software breakpoint instruction to generate
a trap instead, similarly to most other arches, with the generic BUG
code generating the dmesg boilerplate.

This allows bug metadata to be moved to a separate table and reduces
the amount of inline code at BUG() and WARN() sites. This also avoids
clobbering any registers before they can be dumped.

To mitigate the size of the bug table further, this patch makes use of
the existing infrastructure for encoding addresses within the bug table
as 32-bit relative pointers instead of absolute pointers.

(Note: this limits the max kernel size to 2GB.)

Before patch:
[ 3018.338013] lkdtm: Performing direct entry BUG
[ 3018.342445] Kernel bug detected[thesofproject#5]:
[ 3018.345992] CPU: 2 PID: 865 Comm: cat Tainted: G D 6.0.0-rc6+ thesofproject#35

After patch:
[  125.585985] lkdtm: Performing direct entry BUG
[  125.590433] ------------[ cut here ]------------
[  125.595020] kernel BUG at drivers/misc/lkdtm/bugs.c:78!
[  125.600211] Oops - BUG[thesofproject#1]:
[  125.602980] CPU: 3 PID: 410 Comm: cat Not tainted 6.0.0-rc6+ thesofproject#36

Out-of-line file/line data information obtained compared to before.

Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Vamshigopal pushed a commit to Vamshigopal/linux that referenced this pull request Jan 9, 2023
[ Upstream commit bcd7026 ]

By keep sending L2CAP_CONF_REQ packets, chan->num_conf_rsp increases
multiple times and eventually it will wrap around the maximum number
(i.e., 255).
This patch prevents this by adding a boundary check with
L2CAP_MAX_CONF_RSP

Btmon log:
Bluetooth monitor ver 5.64
= Note: Linux version 6.1.0-rc2 (x86_64)                               0.264594
= Note: Bluetooth subsystem version 2.22                               0.264636
@ MGMT Open: btmon (privileged) version 1.22                  {0x0001} 0.272191
= New Index: 00:00:00:00:00:00 (Primary,Virtual,hci0)          [hci0] 13.877604
@ RAW Open: 9496 (privileged) version 2.22                   {0x0002} 13.890741
= Open Index: 00:00:00:00:00:00                                [hci0] 13.900426
(...)
> ACL Data RX: Handle 200 flags 0x00 dlen 1033             thesofproject#32 [hci0] 14.273106
        invalid packet size (12 != 1033)
        08 00 01 00 02 01 04 00 01 10 ff ff              ............
> ACL Data RX: Handle 200 flags 0x00 dlen 1547             thesofproject#33 [hci0] 14.273561
        invalid packet size (14 != 1547)
        0a 00 01 00 04 01 06 00 40 00 00 00 00 00        ........@.....
> ACL Data RX: Handle 200 flags 0x00 dlen 2061             thesofproject#34 [hci0] 14.274390
        invalid packet size (16 != 2061)
        0c 00 01 00 04 01 08 00 40 00 00 00 00 00 00 04  ........@.......
> ACL Data RX: Handle 200 flags 0x00 dlen 2061             thesofproject#35 [hci0] 14.274932
        invalid packet size (16 != 2061)
        0c 00 01 00 04 01 08 00 40 00 00 00 07 00 03 00  ........@.......
= bluetoothd: Bluetooth daemon 5.43                                   14.401828
> ACL Data RX: Handle 200 flags 0x00 dlen 1033             thesofproject#36 [hci0] 14.275753
        invalid packet size (12 != 1033)
        08 00 01 00 04 01 04 00 40 00 00 00              ........@...

Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
bardliao pushed a commit to bardliao/linux that referenced this pull request Aug 22, 2024
Ignore the userspace provided x2APIC ID when fixing up APIC state for
KVM_SET_LAPIC, i.e. make the x2APIC fully readonly in KVM.  Commit
a92e254 ("KVM: x86: use hardware-compatible format for APIC ID
register"), which added the fixup, didn't intend to allow userspace to
modify the x2APIC ID.  In fact, that commit is when KVM first started
treating the x2APIC ID as readonly, apparently to fix some race:

 static inline u32 kvm_apic_id(struct kvm_lapic *apic)
 {
-       return (kvm_lapic_get_reg(apic, APIC_ID) >> 24) & 0xff;
+       /* To avoid a race between apic_base and following APIC_ID update when
+        * switching to x2apic_mode, the x2apic mode returns initial x2apic id.
+        */
+       if (apic_x2apic_mode(apic))
+               return apic->vcpu->vcpu_id;
+
+       return kvm_lapic_get_reg(apic, APIC_ID) >> 24;
 }

Furthermore, KVM doesn't support delivering interrupts to vCPUs with a
modified x2APIC ID, but KVM *does* return the modified value on a guest
RDMSR and for KVM_GET_LAPIC.  I.e. no remotely sane setup can actually
work with a modified x2APIC ID.

Making the x2APIC ID fully readonly fixes a WARN in KVM's optimized map
calculation, which expects the LDR to align with the x2APIC ID.

  WARNING: CPU: 2 PID: 958 at arch/x86/kvm/lapic.c:331 kvm_recalculate_apic_map+0x609/0xa00 [kvm]
  CPU: 2 PID: 958 Comm: recalc_apic_map Not tainted 6.4.0-rc3-vanilla+ thesofproject#35
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.2-1-1 04/01/2014
  RIP: 0010:kvm_recalculate_apic_map+0x609/0xa00 [kvm]
  Call Trace:
   <TASK>
   kvm_apic_set_state+0x1cf/0x5b0 [kvm]
   kvm_arch_vcpu_ioctl+0x1806/0x2100 [kvm]
   kvm_vcpu_ioctl+0x663/0x8a0 [kvm]
   __x64_sys_ioctl+0xb8/0xf0
   do_syscall_64+0x56/0x80
   entry_SYSCALL_64_after_hwframe+0x46/0xb0
  RIP: 0033:0x7fade8b9dd6f

Unfortunately, the WARN can still trigger for other CPUs than the current
one by racing against KVM_SET_LAPIC, so remove it completely.

Reported-by: Michal Luczaj <mhal@rbox.co>
Closes: https://lore.kernel.org/all/814baa0c-1eaa-4503-129f-059917365e80@rbox.co
Reported-by: Haoyu Wu <haoyuwu254@gmail.com>
Closes: https://lore.kernel.org/all/20240126161633.62529-1-haoyuwu254@gmail.com
Reported-by: syzbot+545f1326f405db4e1c3e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000c2a6b9061cbca3c3@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20240802202941.344889-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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