INFO: task syz-executor.1:11029 blocked for more than 143 seconds.
      Not tainted 5.12.0-rc2-next-20210309-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:26576 pid:11029 ppid:  8450 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4353 [inline]
 __schedule+0x90c/0x2150 kernel/sched/core.c:5103
 schedule+0xcf/0x270 kernel/sched/core.c:5182
 io_uring_cancel_files fs/io_uring.c:8678 [inline]
 io_uring_cancel_task_requests+0xc0d/0x1180 fs/io_uring.c:8704
 __io_uring_files_cancel+0x10a/0x1b0 fs/io_uring.c:8812
 io_uring_files_cancel include/linux/io_uring.h:47 [inline]
 do_exit+0x299/0x2a60 kernel/exit.c:780
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x42c/0x2100 kernel/signal.c:2773
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x465f69
RSP: 002b:00007f8dc829b188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: 0000000000000302 RBX: 000000000056bf60 RCX: 0000000000465f69
RDX: 0000000000000000 RSI: 0000000000000302 RDI: 0000000000000004
RBP: 00000000004bfa3f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffd930a1a8f R14: 00007f8dc829b300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1672:
 #0: ffffffff8bf742e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6332
3 locks held by kworker/u4:6/4487:
1 lock held by in:imklog/8145:
 #0: ffff88801830ed70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:961

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

NMI backtrace for cpu 1
CPU: 1 PID: 1672 Comm: khungtaskd Not tainted 5.12.0-rc2-next-20210309-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline]
 watchdog+0xd8e/0xf40 kernel/hung_task.c:338
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9760 Comm: kworker/0:7 Not tainted 5.12.0-rc2-next-20210309-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events toggle_allocation_gate
RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x7/0x60 kernel/kcov.c:197
Code: ff ff b9 ff ff ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 40 00 65 8b 05 c9 11 8e 7e <89> c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 00 f0 01 00 a9
RSP: 0018:ffffc9001655f9c8 EFLAGS: 00000082
RAX: 0000000080000002 RBX: ffff888011520000 RCX: 0000000000000000
RDX: ffff8880305e8000 RSI: ffffffff83e1cd1b RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000007 R09: 000000000001d492
R10: ffffffff83e1cd00 R11: 000000000000003f R12: 00000000ffffffff
R13: 0000000000000007 R14: fffffbfff1b91c64 R15: ffff888011520660
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5039ed5000 CR3: 000000000bc8e000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 cpumask_next lib/cpumask.c:22 [inline]
 cpumask_any_but+0x5c/0x130 lib/cpumask.c:58
 flush_tlb_mm_range+0xb5/0x230 arch/x86/mm/tlb.c:947
 __text_poke+0x590/0x8c0 arch/x86/kernel/alternative.c:944
 text_poke_bp_batch+0x187/0x560 arch/x86/kernel/alternative.c:1190
 text_poke_flush arch/x86/kernel/alternative.c:1347 [inline]
 text_poke_flush arch/x86/kernel/alternative.c:1344 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1354
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:126
 jump_label_update+0x1da/0x400 kernel/jump_label.c:817
 static_key_disable_cpuslocked+0x152/0x1b0 kernel/jump_label.c:207
 static_key_disable+0x16/0x20 kernel/jump_label.c:215
 toggle_allocation_gate mm/kfence/core.c:617 [inline]
 toggle_allocation_gate+0x23a/0x2e0 mm/kfence/core.c:592
 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294