From: syzbot <syzbot+4762dd74e32532cda5ff@syzkaller.appspotmail.com>
To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
syzkaller-bugs@googlegroups.com, tj@kernel.org
Subject: [syzbot] [kernfs?] possible deadlock in __kernfs_remove
Date: Mon, 24 Jun 2024 13:40:25 -0700 [thread overview]
Message-ID: <0000000000007de4c3061ba8ca57@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 626737a5791b Merge tag 'pinctrl-v6.10-2' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=143a383e980000
kernel config: https://syzkaller.appspot.com/x/.config?x=d6b9ee98d841760c
dashboard link: https://syzkaller.appspot.com/bug?extid=4762dd74e32532cda5ff
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-626737a5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1cffeb16f347/vmlinux-626737a5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b20910e32f0e/bzImage-626737a5.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4762dd74e32532cda5ff@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc5-syzkaller-00012-g626737a5791b #0 Not tainted
------------------------------------------------------
udevd/6164 is trying to acquire lock:
ffff88801d0ffe18 (kn->active#5){++++}-{0:0}, at: __kernfs_remove+0x281/0x670 fs/kernfs/dir.c:1486
but task is already holding lock:
ffff888022a504c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_release+0x166/0x6f0 block/bdev.c:1080
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&disk->open_mutex){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
bdev_open+0x41a/0xe50 block/bdev.c:897
bdev_file_open_by_dev block/bdev.c:1011 [inline]
bdev_file_open_by_dev+0x17d/0x210 block/bdev.c:986
disk_scan_partitions+0x1ed/0x320 block/genhd.c:367
device_add_disk+0xe97/0x1250 block/genhd.c:510
pmem_attach_disk+0x9fe/0x1400 drivers/nvdimm/pmem.c:578
nd_pmem_probe+0x1a9/0x1f0 drivers/nvdimm/pmem.c:651
nvdimm_bus_probe+0x169/0x5d0 drivers/nvdimm/bus.c:91
call_driver_probe drivers/base/dd.c:578 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:656
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:798
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:828
__driver_attach+0x283/0x580 drivers/base/dd.c:1214
bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:368
bus_add_driver+0x2e9/0x690 drivers/base/bus.c:673
driver_register+0x15c/0x4b0 drivers/base/driver.c:246
__nd_driver_register+0x103/0x1a0 drivers/nvdimm/bus.c:619
do_one_initcall+0x128/0x700 init/main.c:1267
do_initcall_level init/main.c:1329 [inline]
do_initcalls init/main.c:1345 [inline]
do_basic_setup init/main.c:1364 [inline]
kernel_init_freeable+0x69d/0xca0 init/main.c:1578
kernel_init+0x1c/0x2b0 init/main.c:1467
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #1 (&nvdimm_namespace_key){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
device_lock include/linux/device.h:1009 [inline]
uevent_show+0x188/0x3b0 drivers/base/core.c:2743
dev_attr_show+0x53/0xe0 drivers/base/core.c:2437
sysfs_kf_seq_show+0x23e/0x410 fs/sysfs/file.c:59
seq_read_iter+0x4fa/0x12c0 fs/seq_file.c:230
kernfs_fop_read_iter+0x41a/0x590 fs/kernfs/file.c:279
new_sync_read fs/read_write.c:395 [inline]
vfs_read+0x869/0xbd0 fs/read_write.c:476
ksys_read+0x12f/0x260 fs/read_write.c:619
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (kn->active#5){++++}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
kernfs_drain+0x48f/0x590 fs/kernfs/dir.c:500
__kernfs_remove+0x281/0x670 fs/kernfs/dir.c:1486
kernfs_remove_by_name_ns+0xb2/0x130 fs/kernfs/dir.c:1694
sysfs_remove_file include/linux/sysfs.h:773 [inline]
device_remove_file drivers/base/core.c:3061 [inline]
device_remove_file drivers/base/core.c:3057 [inline]
device_del+0x381/0x9f0 drivers/base/core.c:3866
drop_partition+0x109/0x1c0 block/partitions/core.c:273
bdev_disk_changed+0x24d/0x14f0 block/partitions/core.c:664
__loop_clr_fd+0x392/0x850 drivers/block/loop.c:1208
lo_release+0x188/0x1c0 drivers/block/loop.c:1758
blkdev_put_whole+0xad/0xf0 block/bdev.c:673
bdev_release+0x496/0x6f0 block/bdev.c:1096
blkdev_release+0x15/0x20 block/fops.c:623
__fput+0x408/0xbb0 fs/file_table.c:422
__fput_sync+0x47/0x50 fs/file_table.c:507
__do_sys_close fs/open.c:1555 [inline]
__se_sys_close fs/open.c:1540 [inline]
__x64_sys_close+0x86/0x100 fs/open.c:1540
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Chain exists of:
kn->active#5 --> &nvdimm_namespace_key --> &disk->open_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&disk->open_mutex);
lock(&nvdimm_namespace_key);
lock(&disk->open_mutex);
lock(kn->active#5);
*** DEADLOCK ***
1 lock held by udevd/6164:
#0: ffff888022a504c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_release+0x166/0x6f0 block/bdev.c:1080
stack backtrace:
CPU: 1 PID: 6164 Comm: udevd Not tainted 6.10.0-rc5-syzkaller-00012-g626737a5791b #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
kernfs_drain+0x48f/0x590 fs/kernfs/dir.c:500
__kernfs_remove+0x281/0x670 fs/kernfs/dir.c:1486
kernfs_remove_by_name_ns+0xb2/0x130 fs/kernfs/dir.c:1694
sysfs_remove_file include/linux/sysfs.h:773 [inline]
device_remove_file drivers/base/core.c:3061 [inline]
device_remove_file drivers/base/core.c:3057 [inline]
device_del+0x381/0x9f0 drivers/base/core.c:3866
drop_partition+0x109/0x1c0 block/partitions/core.c:273
bdev_disk_changed+0x24d/0x14f0 block/partitions/core.c:664
__loop_clr_fd+0x392/0x850 drivers/block/loop.c:1208
lo_release+0x188/0x1c0 drivers/block/loop.c:1758
blkdev_put_whole+0xad/0xf0 block/bdev.c:673
bdev_release+0x496/0x6f0 block/bdev.c:1096
blkdev_release+0x15/0x20 block/fops.c:623
__fput+0x408/0xbb0 fs/file_table.c:422
__fput_sync+0x47/0x50 fs/file_table.c:507
__do_sys_close fs/open.c:1555 [inline]
__se_sys_close fs/open.c:1540 [inline]
__x64_sys_close+0x86/0x100 fs/open.c:1540
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feede7170a8
Code: 48 8b 05 83 9d 0d 00 64 c7 00 16 00 00 00 83 c8 ff 48 83 c4 20 5b c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 5b 48 8b 15 51 9d 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffcb56bae78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007feedeab80e0 RCX: 00007feede7170a8
RDX: 000055e713b8acf1 RSI: 00007ffcb56ba678 RDI: 0000000000000008
RBP: 000055e24da11ce0 R08: 0000000000000006 R09: 7dad85b31cc777c1
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000002
R13: 000055e24da17d80 R14: 0000000000000008 R15: 000055e24d9c72c0
</TASK>
udevd[6164]: inotify_add_watch(7, /dev/loop1p4, 10) failed: No such file or directory
I/O error, dev loop3, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
---
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next reply other threads:[~2024-06-24 20:40 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-06-24 20:40 syzbot [this message]
2024-06-24 23:27 ` [syzbot] [kernfs?] possible deadlock in __kernfs_remove Tetsuo Handa
2024-06-25 2:26 ` Dan Williams
2024-06-24 23:41 ` syzbot
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