INFO: task kworker/u4:9:752 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/u4:9 state:D stack:24864 pid: 752 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:9582 [inline] io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9612 io_ring_exit_work+0x137/0x19a0 fs/io_uring.c:9412 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: ffffffff8b97fe60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/6437: #0: ffff88807bfcf270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 3 locks held by kworker/u4:9/752: #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: ffffc90002f0fdb0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffff88803e3ae0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_iowq fs/io_uring.c:9582 [inline] #2: ffff88803e3ae0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9612 1 lock held by syz-executor.3/9499: 1 lock held by syz-executor.3/9501: ============================================= NMI backtrace for cpu 0 CPU: 0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9501 Comm: syz-executor.3 Not tainted 5.15.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0xde/0x180 mm/kasan/generic.c:189 Code: 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 48 85 d2 74 5e 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 50 80 38 00 <74> f2 eb d4 41 bc 08 00 00 00 48 89 ea 45 29 dc 4d 8d 1c 2c eb 0c RSP: 0018:ffffc9000b2a7890 EFLAGS: 00000046 RAX: fffffbfff1f9f726 RBX: fffffbfff1f9f727 RCX: ffffffff815b0286 RDX: fffffbfff1f9f727 RSI: 0000000000000008 RDI: ffffffff8fcfb930 RBP: fffffbfff1f9f726 R08: 0000000000000000 R09: ffffffff8fcfb937 R10: fffffbfff1f9f726 R11: 0000000000000000 R12: ffff88803d7cdfa0 R13: ffff88803d7cd580 R14: 0000000000040000 R15: 00000000000400a4 FS: 00007f1313dc1700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc9ce9a8000 CR3: 000000002978f000 CR4: 0000000000350ee0 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] hlock_class kernel/locking/lockdep.c:199 [inline] check_wait_context kernel/locking/lockdep.c:4688 [inline] __lock_acquire+0x3e6/0x54a0 kernel/locking/lockdep.c:4965 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __fs_reclaim_acquire mm/page_alloc.c:4539 [inline] fs_reclaim_acquire+0x115/0x160 mm/page_alloc.c:4553 might_alloc include/linux/sched/mm.h:198 [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+0x3b/0x2b0 mm/slub.c:3231 kmalloc include/linux/slab.h:591 [inline] io_add_buffers fs/io_uring.c:4390 [inline] io_provide_buffers fs/io_uring.c:4424 [inline] io_issue_sqe+0x3289/0x7180 fs/io_uring.c:6736 __io_queue_sqe+0x90/0xb50 fs/io_uring.c:6965 io_req_task_submit+0xbf/0x1b0 fs/io_uring.c:2239 tctx_task_work+0x189/0x6c0 fs/io_uring.c:2164 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: 0033:0x7f131686b709 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:00007f1313dc1188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 00000000000002ff RBX: 00007f1316970020 RCX: 00007f131686b709 RDX: 0000000000000000 RSI: 00000000000002ff RDI: 0000000000000005 RBP: 00007f13168c5cb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd09bffa0f R14: 00007f1313dc1300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 74 f2 je 0xfffffff4 2: 48 89 c2 mov %rax,%rdx 5: b8 01 00 00 00 mov $0x1,%eax a: 48 85 d2 test %rdx,%rdx d: 75 56 jne 0x65 f: 5b pop %rbx 10: 5d pop %rbp 11: 41 5c pop %r12 13: c3 retq 14: 48 85 d2 test %rdx,%rdx 17: 74 5e je 0x77 19: 48 01 ea add %rbp,%rdx 1c: eb 09 jmp 0x27 1e: 48 83 c0 01 add $0x1,%rax 22: 48 39 d0 cmp %rdx,%rax 25: 74 50 je 0x77 27: 80 38 00 cmpb $0x0,(%rax) * 2a: 74 f2 je 0x1e <-- trapping instruction 2c: eb d4 jmp 0x2 2e: 41 bc 08 00 00 00 mov $0x8,%r12d 34: 48 89 ea mov %rbp,%rdx 37: 45 29 dc sub %r11d,%r12d 3a: 4d 8d 1c 2c lea (%r12,%rbp,1),%r11 3e: eb 0c jmp 0x4c