INFO: task kworker/u4:0:8 blocked for more than 143 seconds. Not tainted 5.15.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:0 state:D stack:24856 pid: 8 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_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: 3 locks held by kworker/u4:0/8: #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: ffffc90000cd7db0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffff88808bce80a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_iowq fs/io_uring.c:9570 [inline] #2: ffff88808bce80a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9600 1 lock held by khungtaskd/27: #0: ffffffff8b981ae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/6229: #0: ffff88802482d270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by kworker/u4:5/6984: #0: ffff8880b9c31a58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:474 #1: ffffc900020afdb0 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 1 lock held by syz-executor.4/22591: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-rc6-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: 22591 Comm: syz-executor.4 Not tainted 5.15.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__this_cpu_preempt_check+0x1/0x20 lib/smp_processor_id.c:65 Code: a7 cc cc ff eb a2 0f 1f 00 0f 1f 44 00 00 48 c7 c6 60 2e e4 89 48 c7 c7 a0 2e e4 89 e9 78 fe ff ff 0f 1f 84 00 00 00 00 00 55 <48> 89 fd 0f 1f 44 00 00 48 89 ee 5d 48 c7 c7 e0 2e e4 89 e9 57 fe RSP: 0018:ffffc90018537a28 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 804f887f085599b9 RCX: ffffc90018537a88 RDX: 1ffff1100fde7862 RSI: 0000000000000000 RDI: ffffffff898bffa0 RBP: 1ffff920030a6f49 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000002 R14: ffff88807ef3c318 R15: ffff88807ef3b900 FS: 00007f474347e700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f460e985000 CR3: 000000008c000000 CR4: 0000000000350ef0 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:438 [inline] lock_release+0x3bb/0x720 kernel/locking/lockdep.c:5647 might_alloc include/linux/sched/mm.h:199 [inline] slab_pre_alloc_hook mm/slab.h:492 [inline] slab_alloc_node mm/slub.c:3120 [inline] slab_alloc mm/slub.c:3214 [inline] kmem_cache_alloc_trace+0x42/0x2b0 mm/slub.c:3231 kmalloc include/linux/slab.h:591 [inline] io_add_buffers fs/io_uring.c:4385 [inline] io_provide_buffers fs/io_uring.c:4419 [inline] io_issue_sqe+0x3289/0x7180 fs/io_uring.c:6731 __io_queue_sqe+0x90/0xb50 fs/io_uring.c:6960 io_req_task_submit+0xbf/0x1b0 fs/io_uring.c:2234 tctx_task_work+0x189/0x6c0 fs/io_uring.c:2159 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: 0033:0x7f4745f08a39 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f474347e188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 00000000000002ff RBX: 00007f474600bf60 RCX: 00007f4745f08a39 RDX: 0000000000000000 RSI: 00000000000002ff RDI: 0000000000000003 RBP: 00007f4745f62c5f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffd55420ff R14: 00007f474347e300 R15: 0000000000022000 ---------------- Code disassembly (best guess), 4 bytes skipped: 0: eb a2 jmp 0xffffffa4 2: 0f 1f 00 nopl (%rax) 5: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) a: 48 c7 c6 60 2e e4 89 mov $0xffffffff89e42e60,%rsi 11: 48 c7 c7 a0 2e e4 89 mov $0xffffffff89e42ea0,%rdi 18: e9 78 fe ff ff jmpq 0xfffffe95 1d: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1) 24: 00 25: 55 push %rbp * 26: 48 89 fd mov %rdi,%rbp <-- trapping instruction 29: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 2e: 48 89 ee mov %rbp,%rsi 31: 5d pop %rbp 32: 48 c7 c7 e0 2e e4 89 mov $0xffffffff89e42ee0,%rdi 39: e9 .byte 0xe9 3a: 57 push %rdi 3b: fe .byte 0xfe