syzbot

INFO: task kworker/u4:1:6564 blocked for more than 143 seconds.
      Not tainted 5.15.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:1    state:D stack:28336 pid: 6564 ppid:     2 flags:0x00004000
Workqueue: events_unbound io_ring_exit_work
Call Trace:
 context_switch kernel/sched/core.c:4940 [inline]
 __schedule+0xb44/0x5960 kernel/sched/core.c:6287
 schedule+0xd3/0x270 kernel/sched/core.c:6366
 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x176/0x280 kernel/sched/completion.c:138
 io_ring_exit_work+0x4bb/0x19a0 fs/io_uring.c:9439
 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8b981b20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446
1 lock held by in:imklog/6233:
 #0: ffff888019a89770 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990
2 locks held by kworker/u4:1/6564:
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
 #1: ffffc90002c4fdb0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
1 lock held by syz-executor675/6715:

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xc1d/0xf50 kernel/hung_task.c:295
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6715 Comm: syz-executor675 Not tainted 5.15.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:50 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:342 [inline]
RIP: 0010:deref_stack_reg+0x90/0x150 arch/x86/kernel/unwind_orc.c:352
Code: 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 94 00 00 00 49 39 ed 49 8b 44 24 10 77 13 48 39 e8 76 0e <48> 8d 55 08 48 39 d0 72 05 49 39 d5 72 3b 49 8d 7c 24 28 48 b8 00
RSP: 0018:ffffc90002f7f6e0 EFLAGS: 00000216
RAX: ffffc90002f80000 RBX: ffffc90002f7f830 RCX: ffffffff8df7bced
RDX: 1ffff920005efeff RSI: ffffc90002f7fcd8 RDI: ffffc90002f7f7f8
RBP: ffffc90002f7fcd8 R08: ffffffff8df7bce8 R09: 0000000000000001
R10: fffff520005eff08 R11: 0000000000086089 R12: ffffc90002f7f7e8
R13: ffffc90002f78000 R14: ffffc90002f7f7e8 R15: ffffffff8df7bcec
FS:  00007f04867ea700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000244 CR3: 0000000033f83000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 unwind_next_frame+0xcc3/0x1ce0 arch/x86/kernel/unwind_orc.c:534
 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 ____kasan_kmalloc mm/kasan/common.c:472 [inline]
 __kasan_kmalloc+0xa4/0xd0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:591 [inline]
 io_add_buffers fs/io_uring.c:4382 [inline]
 io_provide_buffers fs/io_uring.c:4416 [inline]
 io_issue_sqe+0x3289/0x7180 fs/io_uring.c:6728
 __io_queue_sqe+0x90/0xb30 fs/io_uring.c:6957
 io_req_task_submit+0xbf/0x1b0 fs/io_uring.c:2231
 tctx_task_work+0x189/0x6c0 fs/io_uring.c:2156
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 tracehook_notify_signal include/linux/tracehook.h:214 [inline]
 handle_signal_work kernel/entry/common.c:146 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x256/0x290 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_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f0486840ac9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 18 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f04867ea2f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: 00000000000002ff RBX: 00007f04868c23e8 RCX: 00007f0486840ac9
RDX: 0000000000000000 RSI: 00000000000002ff RDI: 0000000000000003
RBP: 00007f04868c23e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f04868c23ec
R13: 0000000000000003 R14: 00007f04867ea400 R15: 0000000000022000
----------------
Code disassembly (best guess):
   0:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
   7:	fc ff df
   a:	48 89 fa             	mov    %rdi,%rdx
   d:	48 c1 ea 03          	shr    $0x3,%rdx
  11:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
  15:	0f 85 94 00 00 00    	jne    0xaf
  1b:	49 39 ed             	cmp    %rbp,%r13
  1e:	49 8b 44 24 10       	mov    0x10(%r12),%rax
  23:	77 13                	ja     0x38
  25:	48 39 e8             	cmp    %rbp,%rax
  28:	76 0e                	jbe    0x38
* 2a:	48 8d 55 08          	lea    0x8(%rbp),%rdx <-- trapping instruction
  2e:	48 39 d0             	cmp    %rdx,%rax
  31:	72 05                	jb     0x38
  33:	49 39 d5             	cmp    %rdx,%r13
  36:	72 3b                	jb     0x73
  38:	49 8d 7c 24 28       	lea    0x28(%r12),%rdi
  3d:	48                   	rex.W
  3e:	b8                   	.byte 0xb8