INFO: task kworker/u4:5:1182 blocked for more than 143 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:5 state:D stack:24440 pid: 1182 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common kernel/locking/mutex.c:669 [inline] __mutex_lock+0xa34/0x12f0 kernel/locking/mutex.c:729 io_uring_try_cancel_iowq fs/io_uring.c:9570 [inline] io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9600 io_ring_exit_work+0x137/0x19a0 fs/io_uring.c:9400 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: ffffffff8b97d3a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 3 locks held by kworker/u4:5/1182: #0: ffff888010c74138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c74138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c74138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c74138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c74138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c74138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc90004927db0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffff888083b360a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_iowq fs/io_uring.c:9570 [inline] #2: ffff888083b360a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9600 1 lock held by in:imklog/6239: 1 lock held by syz-executor.3/21138: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-rc3-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: 19131 Comm: kworker/u4:9 Not tainted 5.15.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:__list_add_valid+0x77/0xa0 lib/list_debug.c:35 Code: 48 8b 16 4c 39 e2 0f 85 0d af 23 05 48 39 f5 0f 84 ed ae 23 05 4c 39 e5 0f 84 e4 ae 23 05 48 83 c4 08 b8 01 00 00 00 5d 41 5c 48 89 34 24 e8 2f 94 de fd 48 8b 34 24 eb a1 48 89 f7 48 89 34 RSP: 0018:ffffc9001740fbf8 EFLAGS: 00000086 RAX: 0000000000000001 RBX: 0000000000000402 RCX: dffffc0000000000 RDX: ffffffff8bac02e0 RSI: ffffffff8bac02e0 RDI: ffffffff8bac02e8 RBP: ffffffff8bac02e0 R08: ffffffff8bac02e0 R09: 0000000000000003 R10: fffff52002e81f6e R11: 0000000000000000 R12: ffffc9001740fc88 R13: ffffffff8bac02a0 R14: 0000000000000286 R15: ffffc9001740fca0 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8cc0ec2010 CR3: 000000000b68e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_add include/linux/list.h:67 [inline] list_add include/linux/list.h:86 [inline] __add_wait_queue include/linux/wait.h:181 [inline] prepare_to_wait_event+0x30f/0x690 kernel/sched/wait.c:321 toggle_allocation_gate mm/kfence/core.c:633 [inline] toggle_allocation_gate+0x325/0x390 mm/kfence/core.c:618 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 ---------------- Code disassembly (best guess): 0: 48 8b 16 mov (%rsi),%rdx 3: 4c 39 e2 cmp %r12,%rdx 6: 0f 85 0d af 23 05 jne 0x523af19 c: 48 39 f5 cmp %rsi,%rbp f: 0f 84 ed ae 23 05 je 0x523af02 15: 4c 39 e5 cmp %r12,%rbp 18: 0f 84 e4 ae 23 05 je 0x523af02 1e: 48 83 c4 08 add $0x8,%rsp 22: b8 01 00 00 00 mov $0x1,%eax 27: 5d pop %rbp 28: 41 5c pop %r12 * 2a: c3 retq <-- trapping instruction 2b: 48 89 34 24 mov %rsi,(%rsp) 2f: e8 2f 94 de fd callq 0xfdde9463 34: 48 8b 34 24 mov (%rsp),%rsi 38: eb a1 jmp 0xffffffdb 3a: 48 89 f7 mov %rsi,%rdi 3d: 48 rex.W 3e: 89 .byte 0x89 3f: 34 .byte 0x34