INFO: task kworker/u4:2:154 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/u4:2 state:D stack:24848 pid: 154 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:9567 [inline] io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9597 io_ring_exit_work+0x137/0x19a0 fs/io_uring.c:9397 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 3 locks held by kworker/u4:2/154: #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: ffffc9000116fdb0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffff88803c70a0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_iowq fs/io_uring.c:9567 [inline] #2: ffff88803c70a0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9597 1 lock held by in:imklog/6247: #0: ffff888072e779f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by syz-executor.1/24864: ============================================= NMI backtrace for cpu 0 CPU: 0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 24864 Comm: syz-executor.1 Not tainted 5.15.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_preempt_wakeup+0xa8/0xab0 kernel/sched/fair.c:7136 Code: af 10 02 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7d 10 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e fd 08 00 00 <41> 8b 45 10 be 08 00 00 00 4c 89 ff 89 44 24 04 e8 33 5d 69 00 4c RSP: 0018:ffffc90000dc0c78 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88801d36d640 RCX: 1ffffffff16664de RDX: 1ffff110173a6362 RSI: ffff888036f05580 RDI: ffff8880b9d31b10 RBP: ffff888036f05640 R08: 0000000000009000 R09: ffff888036f05650 R10: 00000000000003b6 R11: 0000000000000001 R12: ffff888036f05580 R13: ffff8880b9d31b00 R14: ffff8880b9d31a40 R15: ffff88801d36d580 FS: 00007f3b72f68700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f387174b000 CR3: 000000003c51a000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: check_preempt_curr+0x121/0x320 kernel/sched/core.c:2093 ttwu_do_wakeup+0x1c/0x770 kernel/sched/core.c:3524 ttwu_queue kernel/sched/core.c:3774 [inline] try_to_wake_up+0x4ff/0x1570 kernel/sched/core.c:4097 autoremove_wake_function+0x12/0x140 kernel/sched/wait.c:409 __wake_up_common+0x147/0x650 kernel/sched/wait.c:108 __wake_up_common_lock+0xd0/0x130 kernel/sched/wait.c:138 irq_work_single+0x120/0x1f0 kernel/irq_work.c:155 irq_work_run_list+0x91/0xc0 kernel/irq_work.c:177 irq_work_run+0x54/0xd0 kernel/irq_work.c:186 __sysvec_irq_work+0x95/0x3d0 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x8e/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:664 RIP: 0010:default_send_IPI_self+0x5d/0xe0 arch/x86/kernel/apic/ipi.c:243 Code: 1a f3 90 0f b6 45 00 84 c0 74 04 3c 03 7e 76 8b 04 25 00 c3 5f ff f6 c4 10 75 e6 81 cb 00 00 04 00 89 df 89 3c 25 00 c3 5f ff <5b> 5d c3 48 c7 c0 40 9a 33 8b 48 ba 00 00 00 00 00 fc ff df 48 c1 RSP: 0018:ffffc90004ad7a18 EFLAGS: 00000206 RAX: 00000000000008fb RBX: 00000000000400f6 RCX: ffffffff812a04c3 RDX: 1ffffffff1667357 RSI: 0000000000000008 RDI: 00000000000400f6 RBP: fffffbffffebf860 R08: 0000000000000000 R09: ffffffff8d6e6d87 R10: fffffbfff1adcdb0 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000020 R14: 0000000000000020 R15: ffffffff81e403d9 arch_irq_work_raise+0x92/0x110 arch/x86/kernel/irq_work.c:31 __irq_work_queue_local kernel/irq_work.c:59 [inline] __irq_work_queue_local+0x133/0x190 kernel/irq_work.c:53 irq_work_queue kernel/irq_work.c:75 [inline] irq_work_queue+0x47/0x80 kernel/irq_work.c:67 __kfence_alloc+0x12d/0xca0 mm/kfence/core.c:772 kfence_alloc include/linux/kfence.h:124 [inline] slab_alloc_node mm/slub.c:3131 [inline] slab_alloc mm/slub.c:3221 [inline] kmem_cache_alloc_trace+0x21b/0x3c0 mm/slub.c:3238 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: 0033:0x7f3b759f2a39 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:00007f3b72f68188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 0000000000001000 RBX: 00007f3b75af5f60 RCX: 00007f3b759f2a39 RDX: 0000000000000000 RSI: 000000000000688c RDI: 0000000000000003 RBP: 00007f3b75a4ce8f R08: 0000000000000000 R09: 00000000ffffffa7 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3b76029b2f R14: 00007f3b72f68300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: af scas %es:(%rdi),%eax 1: 10 02 adc %al,(%rdx) 3: 00 00 add %al,(%rax) 5: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax c: fc ff df f: 49 8d 7d 10 lea 0x10(%r13),%rdi 13: 48 89 fa mov %rdi,%rdx 16: 48 c1 ea 03 shr $0x3,%rdx 1a: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax 1e: 84 c0 test %al,%al 20: 74 08 je 0x2a 22: 3c 03 cmp $0x3,%al 24: 0f 8e fd 08 00 00 jle 0x927 * 2a: 41 8b 45 10 mov 0x10(%r13),%eax <-- trapping instruction 2e: be 08 00 00 00 mov $0x8,%esi 33: 4c 89 ff mov %r15,%rdi 36: 89 44 24 04 mov %eax,0x4(%rsp) 3a: e8 33 5d 69 00 callq 0x695d72 3f: 4c rex.WR