[v5.15] possible deadlock in blk_request_module (2)
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syzbot
Jul 8, 2025, 4:34:24 PM7/8/25
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: 3dea0e7f549e Linux 5.15.186
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=130bd582580000
kernel config: https://syzkaller.appspot.com/x/.config?x=644ffcb58c0b09d3
dashboard link: https://syzkaller.appspot.com/bug?extid=c16318db01199828c4ff
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3d73d6f07b0c/disk-3dea0e7f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4064de18c9e9/vmlinux-3dea0e7f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/069c7b1e74a9/bzImage-3dea0e7f.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c16318...@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
5.15.186-syzkaller #0 Not tainted
------------------------------------------------------
syz.3.1789/13699 is trying to acquire lock:
ffffffff8c6fb1e8 (major_names_lock){+.+.}-{3:3}, at: blk_probe_dev block/genhd.c:682 [inline]
ffffffff8c6fb1e8 (major_names_lock){+.+.}-{3:3}, at: blk_request_module+0x31/0x290 block/genhd.c:698
but task is already holding lock:
ffffffff8bfd4ce8 (system_transition_mutex/1){+.+.}-{3:3}, at: software_resume+0x7c/0x3b0 kernel/power/hibernate.c:937
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #8 (system_transition_mutex/1){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
software_resume+0x7c/0x3b0 kernel/power/hibernate.c:937
resume_store+0xe4/0x130 kernel/power/hibernate.c:1184
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #7 (&of->mutex){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
kernfs_seq_start+0x51/0x3c0 fs/kernfs/file.c:112
seq_read_iter+0x3c4/0xd50 fs/seq_file.c:225
call_read_iter include/linux/fs.h:2166 [inline]
new_sync_read fs/read_write.c:404 [inline]
vfs_read+0x725/0xcf0 fs/read_write.c:485
ksys_read+0x14d/0x250 fs/read_write.c:623
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #6 (&p->lock){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
seq_read_iter+0xad/0xd50 fs/seq_file.c:182
proc_reg_read_iter+0x1a9/0x270 fs/proc/inode.c:300
call_read_iter include/linux/fs.h:2166 [inline]
generic_file_splice_read+0x3a2/0x590 fs/splice.c:311
do_splice_to fs/splice.c:796 [inline]
splice_direct_to_actor+0x413/0xb50 fs/splice.c:870
do_splice_direct+0x1b9/0x2c0 fs/splice.c:979
do_sendfile+0x5d5/0xec0 fs/read_write.c:1249
__do_sys_sendfile64 fs/read_write.c:1317 [inline]
__se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1303
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #5 (sb_writers#3){.+.+}-{0:0}:
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1811 [inline]
sb_start_write include/linux/fs.h:1881 [inline]
file_start_write include/linux/fs.h:3042 [inline]
lo_write_bvec+0x193/0x770 drivers/block/loop.c:315
lo_write_simple drivers/block/loop.c:338 [inline]
do_req_filebacked drivers/block/loop.c:656 [inline]
loop_handle_cmd drivers/block/loop.c:2235 [inline]
loop_process_work+0x1d62/0x2480 drivers/block/loop.c:2275
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
-> #4 ((work_completion)(&worker->work)){+.+.}-{0:0}:
process_one_work+0x7bf/0x1000 kernel/workqueue.c:2286
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
-> #3 ((wq_completion)loop8){+.+.}-{0:0}:
flush_workqueue+0x142/0x1380 kernel/workqueue.c:2830
drain_workqueue+0xcf/0x380 kernel/workqueue.c:2995
destroy_workqueue+0x7b/0xb20 kernel/workqueue.c:4439
__loop_clr_fd+0x234/0xb90 drivers/block/loop.c:1384
blkdev_put_whole block/bdev.c:692 [inline]
blkdev_put+0x53f/0x7d0 block/bdev.c:957
deactivate_locked_super+0x93/0xf0 fs/super.c:335
cleanup_mnt+0x418/0x4d0 fs/namespace.c:1139
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #2 (&lo->lo_mutex){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_killable_nested+0x17/0x20 kernel/locking/mutex.c:758
lo_open+0x6a/0x100 drivers/block/loop.c:2056
blkdev_get_whole+0x90/0x390 block/bdev.c:669
blkdev_get_by_dev+0x2d0/0xa60 block/bdev.c:827
blkdev_open+0x12d/0x2c0 block/fops.c:466
do_dentry_open+0x7ff/0xf80 fs/open.c:826
do_open fs/namei.c:3608 [inline]
path_openat+0x2682/0x2f30 fs/namei.c:3742
do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
do_sys_openat2+0x142/0x4a0 fs/open.c:1253
do_sys_open fs/open.c:1269 [inline]
__do_sys_openat fs/open.c:1285 [inline]
__se_sys_openat fs/open.c:1280 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1280
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #1 (&disk->open_mutex){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
bd_register_pending_holders+0x33/0x310 block/holder.c:161
device_add_disk+0x5a7/0xd40 block/genhd.c:486
add_disk include/linux/genhd.h:200 [inline]
loop_add+0x5f2/0x8a0 drivers/block/loop.c:2431
blk_probe_dev block/genhd.c:685 [inline]
blk_request_module+0x26e/0x290 block/genhd.c:-1
blkdev_get_no_open+0x38/0x1d0 block/bdev.c:740
blkdev_get_by_dev+0x77/0xa60 block/bdev.c:807
blkdev_open+0x12d/0x2c0 block/fops.c:466
do_dentry_open+0x7ff/0xf80 fs/open.c:826
do_open fs/namei.c:3608 [inline]
path_openat+0x2682/0x2f30 fs/namei.c:3742
do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
do_sys_openat2+0x142/0x4a0 fs/open.c:1253
do_sys_open fs/open.c:1269 [inline]
__do_sys_creat fs/open.c:1345 [inline]
__se_sys_creat fs/open.c:1339 [inline]
__x64_sys_creat+0x8c/0xb0 fs/open.c:1339
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #0 (major_names_lock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
blk_probe_dev block/genhd.c:682 [inline]
blk_request_module+0x31/0x290 block/genhd.c:698
blkdev_get_no_open+0x38/0x1d0 block/bdev.c:740
blkdev_get_by_dev+0x77/0xa60 block/bdev.c:807
swsusp_check+0x9b/0x2a0 kernel/power/swap.c:1526
software_resume+0xc6/0x3b0 kernel/power/hibernate.c:982
resume_store+0xe4/0x130 kernel/power/hibernate.c:1184
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
other info that might help us debug this:
Chain exists of:
major_names_lock --> &of->mutex --> system_transition_mutex/1
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(system_transition_mutex/1);
lock(&of->mutex);
lock(system_transition_mutex/1);
lock(major_names_lock);
*** DEADLOCK ***
5 locks held by syz.3.1789/13699:
#0: ffff888022319270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2bf/0x370 fs/file.c:1058
#1: ffff88807f1c0460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
#2: ffff88805f119488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#3: ffff888144bfd830 (kn->active#866){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x208/0x4c0 fs/kernfs/file.c:288
#4: ffffffff8bfd4ce8 (system_transition_mutex/1){+.+.}-{3:3}, at: software_resume+0x7c/0x3b0 kernel/power/hibernate.c:937
stack backtrace:
CPU: 0 PID: 13699 Comm: syz.3.1789 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
blk_probe_dev block/genhd.c:682 [inline]
blk_request_module+0x31/0x290 block/genhd.c:698
blkdev_get_no_open+0x38/0x1d0 block/bdev.c:740
blkdev_get_by_dev+0x77/0xa60 block/bdev.c:807
swsusp_check+0x9b/0x2a0 kernel/power/swap.c:1526
software_resume+0xc6/0x3b0 kernel/power/hibernate.c:982
resume_store+0xe4/0x130 kernel/power/hibernate.c:1184
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fee69700929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fee67547038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fee69928080 RCX: 00007fee69700929
RDX: 0000000000000012 RSI: 0000200000000040 RDI: 0000000000000009
RBP: 00007fee69782b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fee69928080 R15: 00007ffd5befb418
</TASK>
block device autoloading is deprecated and will be removed.
PM: Image not found (code -22)
---
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If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
#syz undup
syzbot found the following issue on:
HEAD commit: 3dea0e7f549e Linux 5.15.186
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=130bd582580000
kernel config: https://syzkaller.appspot.com/x/.config?x=644ffcb58c0b09d3
dashboard link: https://syzkaller.appspot.com/bug?extid=c16318db01199828c4ff
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3d73d6f07b0c/disk-3dea0e7f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4064de18c9e9/vmlinux-3dea0e7f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/069c7b1e74a9/bzImage-3dea0e7f.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c16318...@syzkaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
5.15.186-syzkaller #0 Not tainted
------------------------------------------------------
syz.3.1789/13699 is trying to acquire lock:
ffffffff8c6fb1e8 (major_names_lock){+.+.}-{3:3}, at: blk_probe_dev block/genhd.c:682 [inline]
ffffffff8c6fb1e8 (major_names_lock){+.+.}-{3:3}, at: blk_request_module+0x31/0x290 block/genhd.c:698
but task is already holding lock:
ffffffff8bfd4ce8 (system_transition_mutex/1){+.+.}-{3:3}, at: software_resume+0x7c/0x3b0 kernel/power/hibernate.c:937
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #8 (system_transition_mutex/1){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
software_resume+0x7c/0x3b0 kernel/power/hibernate.c:937
resume_store+0xe4/0x130 kernel/power/hibernate.c:1184
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #7 (&of->mutex){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
kernfs_seq_start+0x51/0x3c0 fs/kernfs/file.c:112
seq_read_iter+0x3c4/0xd50 fs/seq_file.c:225
call_read_iter include/linux/fs.h:2166 [inline]
new_sync_read fs/read_write.c:404 [inline]
vfs_read+0x725/0xcf0 fs/read_write.c:485
ksys_read+0x14d/0x250 fs/read_write.c:623
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #6 (&p->lock){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
seq_read_iter+0xad/0xd50 fs/seq_file.c:182
proc_reg_read_iter+0x1a9/0x270 fs/proc/inode.c:300
call_read_iter include/linux/fs.h:2166 [inline]
generic_file_splice_read+0x3a2/0x590 fs/splice.c:311
do_splice_to fs/splice.c:796 [inline]
splice_direct_to_actor+0x413/0xb50 fs/splice.c:870
do_splice_direct+0x1b9/0x2c0 fs/splice.c:979
do_sendfile+0x5d5/0xec0 fs/read_write.c:1249
__do_sys_sendfile64 fs/read_write.c:1317 [inline]
__se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1303
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #5 (sb_writers#3){.+.+}-{0:0}:
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1811 [inline]
sb_start_write include/linux/fs.h:1881 [inline]
file_start_write include/linux/fs.h:3042 [inline]
lo_write_bvec+0x193/0x770 drivers/block/loop.c:315
lo_write_simple drivers/block/loop.c:338 [inline]
do_req_filebacked drivers/block/loop.c:656 [inline]
loop_handle_cmd drivers/block/loop.c:2235 [inline]
loop_process_work+0x1d62/0x2480 drivers/block/loop.c:2275
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
-> #4 ((work_completion)(&worker->work)){+.+.}-{0:0}:
process_one_work+0x7bf/0x1000 kernel/workqueue.c:2286
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
-> #3 ((wq_completion)loop8){+.+.}-{0:0}:
flush_workqueue+0x142/0x1380 kernel/workqueue.c:2830
drain_workqueue+0xcf/0x380 kernel/workqueue.c:2995
destroy_workqueue+0x7b/0xb20 kernel/workqueue.c:4439
__loop_clr_fd+0x234/0xb90 drivers/block/loop.c:1384
blkdev_put_whole block/bdev.c:692 [inline]
blkdev_put+0x53f/0x7d0 block/bdev.c:957
deactivate_locked_super+0x93/0xf0 fs/super.c:335
cleanup_mnt+0x418/0x4d0 fs/namespace.c:1139
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #2 (&lo->lo_mutex){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_killable_nested+0x17/0x20 kernel/locking/mutex.c:758
lo_open+0x6a/0x100 drivers/block/loop.c:2056
blkdev_get_whole+0x90/0x390 block/bdev.c:669
blkdev_get_by_dev+0x2d0/0xa60 block/bdev.c:827
blkdev_open+0x12d/0x2c0 block/fops.c:466
do_dentry_open+0x7ff/0xf80 fs/open.c:826
do_open fs/namei.c:3608 [inline]
path_openat+0x2682/0x2f30 fs/namei.c:3742
do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
do_sys_openat2+0x142/0x4a0 fs/open.c:1253
do_sys_open fs/open.c:1269 [inline]
__do_sys_openat fs/open.c:1285 [inline]
__se_sys_openat fs/open.c:1280 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1280
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #1 (&disk->open_mutex){+.+.}-{3:3}:
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
bd_register_pending_holders+0x33/0x310 block/holder.c:161
device_add_disk+0x5a7/0xd40 block/genhd.c:486
add_disk include/linux/genhd.h:200 [inline]
loop_add+0x5f2/0x8a0 drivers/block/loop.c:2431
blk_probe_dev block/genhd.c:685 [inline]
blk_request_module+0x26e/0x290 block/genhd.c:-1
blkdev_get_no_open+0x38/0x1d0 block/bdev.c:740
blkdev_get_by_dev+0x77/0xa60 block/bdev.c:807
blkdev_open+0x12d/0x2c0 block/fops.c:466
do_dentry_open+0x7ff/0xf80 fs/open.c:826
do_open fs/namei.c:3608 [inline]
path_openat+0x2682/0x2f30 fs/namei.c:3742
do_filp_open+0x1b3/0x3e0 fs/namei.c:3769
do_sys_openat2+0x142/0x4a0 fs/open.c:1253
do_sys_open fs/open.c:1269 [inline]
__do_sys_creat fs/open.c:1345 [inline]
__se_sys_creat fs/open.c:1339 [inline]
__x64_sys_creat+0x8c/0xb0 fs/open.c:1339
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #0 (major_names_lock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
blk_probe_dev block/genhd.c:682 [inline]
blk_request_module+0x31/0x290 block/genhd.c:698
blkdev_get_no_open+0x38/0x1d0 block/bdev.c:740
blkdev_get_by_dev+0x77/0xa60 block/bdev.c:807
swsusp_check+0x9b/0x2a0 kernel/power/swap.c:1526
software_resume+0xc6/0x3b0 kernel/power/hibernate.c:982
resume_store+0xe4/0x130 kernel/power/hibernate.c:1184
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
other info that might help us debug this:
Chain exists of:
major_names_lock --> &of->mutex --> system_transition_mutex/1
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(system_transition_mutex/1);
lock(&of->mutex);
lock(system_transition_mutex/1);
lock(major_names_lock);
*** DEADLOCK ***
5 locks held by syz.3.1789/13699:
#0: ffff888022319270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2bf/0x370 fs/file.c:1058
#1: ffff88807f1c0460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
#2: ffff88805f119488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#3: ffff888144bfd830 (kn->active#866){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x208/0x4c0 fs/kernfs/file.c:288
#4: ffffffff8bfd4ce8 (system_transition_mutex/1){+.+.}-{3:3}, at: software_resume+0x7c/0x3b0 kernel/power/hibernate.c:937
stack backtrace:
CPU: 0 PID: 13699 Comm: syz.3.1789 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
__mutex_lock_common+0x1eb/0x2390 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
blk_probe_dev block/genhd.c:682 [inline]
blk_request_module+0x31/0x290 block/genhd.c:698
blkdev_get_no_open+0x38/0x1d0 block/bdev.c:740
blkdev_get_by_dev+0x77/0xa60 block/bdev.c:807
swsusp_check+0x9b/0x2a0 kernel/power/swap.c:1526
software_resume+0xc6/0x3b0 kernel/power/hibernate.c:982
resume_store+0xe4/0x130 kernel/power/hibernate.c:1184
kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x712/0xd00 fs/read_write.c:594
ksys_write+0x14d/0x250 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fee69700929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fee67547038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fee69928080 RCX: 00007fee69700929
RDX: 0000000000000012 RSI: 0000200000000040 RDI: 0000000000000009
RBP: 00007fee69782b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fee69928080 R15: 00007ffd5befb418
</TASK>
block device autoloading is deprecated and will be removed.
PM: Image not found (code -22)
---
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