INFO: task kworker/u4:5:1048 blocked for more than 143 seconds.
      Not tainted 5.16.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:5    state:D stack:26744 pid: 1048 ppid:     2 flags:0x00004000
Workqueue: events_unbound io_ring_exit_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326
 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+0x174/0x270 kernel/sched/completion.c:138
 io_ring_exit_work+0xbaf/0xbd0 fs/io_uring.c:9526
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/26:
 #0: ffffffff8bb83e20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458
2 locks held by kworker/u4:5/1048:
 #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:635 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2269
 #1: ffffc90004dbfdb0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2273
2 locks held by getty/3286:
 #0: ffff88807f0a0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002b962e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113

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

NMI backtrace for cpu 1
CPU: 1 PID: 26 Comm: khungtaskd Not tainted 5.16.0-rc6-syzkaller #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
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 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+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 2962 Comm: klogd Not tainted 5.16.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:unwind_next_frame+0x670/0x1ce0 arch/x86/kernel/unwind_orc.c:530
Code: 4c 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 8f 10 00 00 41 0f b6 40 04 83 e0 0f 3c 09 0f 84 b0 0d 00 00 41 0f b6 40 05 83 e0 03 <3c> 01 0f 84 23 09 00 00 3c 02 0f 84 7f 08 00 00 84 c0 0f 84 31 06
RSP: 0018:ffffc90000007838 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 1ffff92000000f0f RCX: ffffffff8ea4c135
RDX: ffffc90001b0f3d8 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffff8ea4c130 R09: 0000000000000001
R10: fffff52000000f2d R11: 000000000008808a R12: ffffc90000007958
R13: ffffc90000007945 R14: ffffc90000007910 R15: ffffffff8ea4c134
FS:  00007f2c5a662800(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005556085b3f38 CR3: 000000007f17d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xf5/0x120 mm/kasan/generic.c:348
 insert_work+0x48/0x370 kernel/workqueue.c:1354
 __queue_work+0x5ca/0xee0 kernel/workqueue.c:1520
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1461 [inline]
 __run_timers.part.0+0x49f/0xa20 kernel/time/timer.c:1734
 __run_timers kernel/time/timer.c:1715 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:deref_stack_reg+0x15/0x150 arch/x86/kernel/unwind_orc.c:351
Code: 48 ff ff ff 48 89 0c 24 e8 88 82 8a 00 48 8b 0c 24 eb 9d 66 90 48 b8 00 00 00 00 00 fc ff df 41 55 41 54 49 89 fc 55 48 89 f5 <53> 48 89 d3 48 89 fa 48 c1 ea 03 48 83 ec 08 0f b6 04 02 84 c0 74
RSP: 0018:ffffc90001b0f488 EFLAGS: 00000287
RAX: dffffc0000000000 RBX: 1ffff92000361e9d RCX: 0000000000000000
RDX: ffffc90001b0f5c0 RSI: ffffc90001b0fb60 RDI: ffffc90001b0f580
RBP: ffffc90001b0fb60 R08: ffffffff8e81a9fe R09: 0000000000000001
R10: fffff52000361ebb R11: 000000000008808a R12: ffffc90001b0f580
R13: ffffc90001b0f5b5 R14: ffffc90001b0f580 R15: ffffc90001b0f5b4
 unwind_next_frame+0x13f9/0x1ce0 arch/x86/kernel/unwind_orc.c:600
 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122
 save_stack+0x151/0x1e0 mm/page_owner.c:119
 __reset_page_owner+0x5d/0x180 mm/page_owner.c:140
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1338 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1389
 free_unref_page_prepare mm/page_alloc.c:3309 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3388
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:259 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:3234 [inline]
 kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3270
 __alloc_skb+0x215/0x340 net/core/skbuff.c:414
 alloc_skb include/linux/skbuff.h:1126 [inline]
 alloc_skb_with_frags+0x93/0x620 net/core/skbuff.c:6078
 sock_alloc_send_pskb+0x783/0x910 net/core/sock.c:2575
 unix_dgram_sendmsg+0x3ec/0x1950 net/unix/af_unix.c:1811
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 __sys_sendto+0x21c/0x320 net/socket.c:2036
 __do_sys_sendto net/socket.c:2048 [inline]
 __se_sys_sendto net/socket.c:2044 [inline]
 __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2044
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f2c5a7fe0ac
Code: 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 19 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 64 c3 0f 1f 00 55 48 83 ec 20 48 89 54 24 10
RSP: 002b:00007fff94d16e68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2c5a7fe0ac
RDX: 000000000000004d RSI: 000055ac5005c6c0 RDI: 0000000000000003
RBP: 000055ac50057910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000014
R13: 0000000000000001 R14: 00007f2c5a97977d R15: 00007fff94d16f78
 </TASK>
----------------
Code disassembly (best guess):
   0:	4c 89 fa             	mov    %r15,%rdx
   3:	83 e2 07             	and    $0x7,%edx
   6:	38 d0                	cmp    %dl,%al
   8:	7f 08                	jg     0x12
   a:	84 c0                	test   %al,%al
   c:	0f 85 8f 10 00 00    	jne    0x10a1
  12:	41 0f b6 40 04       	movzbl 0x4(%r8),%eax
  17:	83 e0 0f             	and    $0xf,%eax
  1a:	3c 09                	cmp    $0x9,%al
  1c:	0f 84 b0 0d 00 00    	je     0xdd2
  22:	41 0f b6 40 05       	movzbl 0x5(%r8),%eax
  27:	83 e0 03             	and    $0x3,%eax
* 2a:	3c 01                	cmp    $0x1,%al <-- trapping instruction
  2c:	0f 84 23 09 00 00    	je     0x955
  32:	3c 02                	cmp    $0x2,%al
  34:	0f 84 7f 08 00 00    	je     0x8b9
  3a:	84 c0                	test   %al,%al
  3c:	0f                   	.byte 0xf
  3d:	84 31                	test   %dh,(%rcx)
  3f:	06                   	(bad)