======================================================
WARNING: possible circular locking dependency detected
5.17.0-rc6-syzkaller-00054-gfb184c4af9b9 #0 Not tainted
------------------------------------------------------
syz-executor.0/3626 is trying to acquire lock:
ffff8880792d2938 ((wq_completion)loop0){+.+.}-{0:0}, at: flush_workqueue+0xe1/0x13a0 kernel/workqueue.c:2824

but task is already holding lock:
ffff88806ebf5118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x99/0x950 block/bdev.c:902

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #6 (&disk->open_mutex){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:600 [inline]
       __mutex_lock+0x12f/0x12f0 kernel/locking/mutex.c:733
       blkdev_get_by_dev.part.0+0x40e/0xc70 block/bdev.c:804
       blkdev_get_by_dev+0x6b/0x80 block/bdev.c:847
       swsusp_check+0x97/0x420 kernel/power/swap.c:1526
       software_resume.part.0+0x102/0x1f0 kernel/power/hibernate.c:979
       software_resume kernel/power/hibernate.c:86 [inline]
       resume_store+0x161/0x190 kernel/power/hibernate.c:1181
       kobj_attr_store+0x50/0x80 lib/kobject.c:856
       sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:136
       kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:296
       call_write_iter include/linux/fs.h:2074 [inline]
       new_sync_write+0x431/0x660 fs/read_write.c:503
       vfs_write+0x7cd/0xae0 fs/read_write.c:590
       ksys_write+0x12d/0x250 fs/read_write.c:643
       do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
       __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
       do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
       entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

-> #5 (system_transition_mutex/1){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:600 [inline]
       __mutex_lock+0x12f/0x12f0 kernel/locking/mutex.c:733
       software_resume.part.0+0x19/0x1f0 kernel/power/hibernate.c:934
       software_resume kernel/power/hibernate.c:86 [inline]
       resume_store+0x161/0x190 kernel/power/hibernate.c:1181
       kobj_attr_store+0x50/0x80 lib/kobject.c:856
       sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:136
       kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:296
       call_write_iter include/linux/fs.h:2074 [inline]
       new_sync_write+0x431/0x660 fs/read_write.c:503
       vfs_write+0x7cd/0xae0 fs/read_write.c:590
       ksys_write+0x12d/0x250 fs/read_write.c:643
       do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
       __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
       do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
       entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

-> #4 (&of->mutex){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:600 [inline]
       __mutex_lock+0x12f/0x12f0 kernel/locking/mutex.c:733
       kernfs_fop_write_iter+0x28c/0x610 fs/kernfs/file.c:287
       call_write_iter include/linux/fs.h:2074 [inline]
       do_iter_readv_writev+0x47a/0x750 fs/read_write.c:725
       do_iter_write+0x188/0x710 fs/read_write.c:851
       vfs_iter_write+0x70/0xa0 fs/read_write.c:892
       iter_file_splice_write+0x723/0xc70 fs/splice.c:689
       do_splice_from fs/splice.c:767 [inline]
       do_splice+0xb7e/0x1960 fs/splice.c:1079
       __do_splice+0x134/0x250 fs/splice.c:1144
       __do_sys_splice fs/splice.c:1350 [inline]
       __se_sys_splice fs/splice.c:1332 [inline]
       __ia32_sys_splice+0x195/0x250 fs/splice.c:1332
       do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
       __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
       do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
       entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

-> #3 (&pipe->mutex/1){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:600 [inline]
       __mutex_lock+0x12f/0x12f0 kernel/locking/mutex.c:733
       pipe_lock_nested fs/pipe.c:82 [inline]
       pipe_lock+0x5a/0x70 fs/pipe.c:90
       iter_file_splice_write+0x183/0xc70 fs/splice.c:635
       do_splice_from fs/splice.c:767 [inline]
       do_splice+0xb7e/0x1960 fs/splice.c:1079
       __do_splice+0x134/0x250 fs/splice.c:1144
       __do_sys_splice fs/splice.c:1350 [inline]
       __se_sys_splice fs/splice.c:1332 [inline]
       __ia32_sys_splice+0x195/0x250 fs/splice.c:1332
       do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
       __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
       do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
       entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

-> #2 (sb_writers#3){.+.+}-{0:0}:
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1722 [inline]
       sb_start_write include/linux/fs.h:1792 [inline]
       file_start_write include/linux/fs.h:2937 [inline]
       lo_write_bvec drivers/block/loop.c:243 [inline]
       lo_write_simple drivers/block/loop.c:266 [inline]
       do_req_filebacked drivers/block/loop.c:495 [inline]
       loop_handle_cmd drivers/block/loop.c:1852 [inline]
       loop_process_work+0x1499/0x1db0 drivers/block/loop.c:1892
       process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
       worker_thread+0x657/0x1110 kernel/workqueue.c:2454
       kthread+0x2e9/0x3a0 kernel/kthread.c:377
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

-> #1 ((work_completion)(&worker->work)#2){+.+.}-{0:0}:
       process_one_work+0x91b/0x1650 kernel/workqueue.c:2283
       worker_thread+0x657/0x1110 kernel/workqueue.c:2454
       kthread+0x2e9/0x3a0 kernel/kthread.c:377
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

-> #0 ((wq_completion)loop0){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3063 [inline]
       check_prevs_add kernel/locking/lockdep.c:3186 [inline]
       validate_chain kernel/locking/lockdep.c:3801 [inline]
       __lock_acquire+0x2ad4/0x56c0 kernel/locking/lockdep.c:5027
       lock_acquire kernel/locking/lockdep.c:5639 [inline]
       lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604
       flush_workqueue+0x110/0x13a0 kernel/workqueue.c:2827
       drain_workqueue+0x1a5/0x3c0 kernel/workqueue.c:2992
       destroy_workqueue+0x71/0x800 kernel/workqueue.c:4429
       __loop_clr_fd+0x1ab/0xe20 drivers/block/loop.c:1124
       lo_release+0x1ac/0x1f0 drivers/block/loop.c:1756
       blkdev_put_whole block/bdev.c:689 [inline]
       blkdev_put+0x2de/0x950 block/bdev.c:944
       blkdev_close+0x6a/0x80 block/fops.c:517
       __fput+0x286/0x9f0 fs/file_table.c:317
       task_work_run+0xdd/0x1a0 kernel/task_work.c:164
       tracehook_notify_resume include/linux/tracehook.h:188 [inline]
       exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
       exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
       __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
       syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
       __do_fast_syscall_32+0x72/0xf0 arch/x86/entry/common.c:181
       do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
       entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

other info that might help us debug this:

Chain exists of:
  (wq_completion)loop0 --> system_transition_mutex/1 --> &disk->open_mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&disk->open_mutex);
                               lock(system_transition_mutex/1);
                               lock(&disk->open_mutex);
  lock((wq_completion)loop0);

 *** DEADLOCK ***

1 lock held by syz-executor.0/3626:
 #0: ffff88806ebf5118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x99/0x950 block/bdev.c:902

stack backtrace:
CPU: 1 PID: 3626 Comm: syz-executor.0 Not tainted 5.17.0-rc6-syzkaller-00054-gfb184c4af9b9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2143
 check_prev_add kernel/locking/lockdep.c:3063 [inline]
 check_prevs_add kernel/locking/lockdep.c:3186 [inline]
 validate_chain kernel/locking/lockdep.c:3801 [inline]
 __lock_acquire+0x2ad4/0x56c0 kernel/locking/lockdep.c:5027
 lock_acquire kernel/locking/lockdep.c:5639 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604
 flush_workqueue+0x110/0x13a0 kernel/workqueue.c:2827
 drain_workqueue+0x1a5/0x3c0 kernel/workqueue.c:2992
 destroy_workqueue+0x71/0x800 kernel/workqueue.c:4429
 __loop_clr_fd+0x1ab/0xe20 drivers/block/loop.c:1124
 lo_release+0x1ac/0x1f0 drivers/block/loop.c:1756
 blkdev_put_whole block/bdev.c:689 [inline]
 blkdev_put+0x2de/0x950 block/bdev.c:944
 blkdev_close+0x6a/0x80 block/fops.c:517
 __fput+0x286/0x9f0 fs/file_table.c:317
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
 __do_fast_syscall_32+0x72/0xf0 arch/x86/entry/common.c:181
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf6f59549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f75ead30 EFLAGS: 00000282 ORIG_RAX: 0000000000000006
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 00000000f7091000 RDI: 00000000f7091000
RBP: 00000000f700b1b2 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	03 74 c0 01          	add    0x1(%rax,%rax,8),%esi
   4:	10 05 03 74 b8 01    	adc    %al,0x1b87403(%rip)        # 0x1b8740d
   a:	10 06                	adc    %al,(%rsi)
   c:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
  10:	10 07                	adc    %al,(%rdi)
  12:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
  16:	10 08                	adc    %cl,(%rax)
  18:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1c:	00 00                	add    %al,(%rax)
  1e:	00 00                	add    %al,(%rax)
  20:	00 51 52             	add    %dl,0x52(%rcx)
  23:	55                   	push   %rbp
  24:	89 e5                	mov    %esp,%ebp
  26:	0f 34                	sysenter
  28:	cd 80                	int    $0x80
* 2a:	5d                   	pop    %rbp <-- trapping instruction
  2b:	5a                   	pop    %rdx
  2c:	59                   	pop    %rcx
  2d:	c3                   	retq
  2e:	90                   	nop
  2f:	90                   	nop
  30:	90                   	nop
  31:	90                   	nop
  32:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  39:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi