INFO: task kworker/u4:4:1163 blocked for more than 143 seconds. Not tainted 5.15.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:4 state:D stack:20632 pid: 1163 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xc8d/0x1270 kernel/sched/core.c:6287 schedule+0x14b/0x210 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common+0xdff/0x2550 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:743 io_uring_try_cancel_iowq fs/io_uring.c:9529 [inline] io_uring_try_cancel_requests+0x27c/0xc50 fs/io_uring.c:9559 io_ring_exit_work+0x11c/0x1d00 fs/io_uring.c:9359 process_one_work+0x853/0x1140 kernel/workqueue.c:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 Showing all locks held in the system: 1 lock held by khungtaskd/26: #0: ffffffff8c91c180 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/u4:4/1163: #0: ffff888011069138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc9000534fd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffff88807cd540a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_iowq fs/io_uring.c:9529 [inline] #2: ffff88807cd540a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_requests+0x27c/0xc50 fs/io_uring.c:9559 1 lock held by in:imklog/6219: #0: ffff88801a6a34f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:990 1 lock held by syz-executor.4/26141: 2 locks held by syz-executor.4/26148: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 26 Comm: khungtaskd Not tainted 5.15.0-rc2-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+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x16a/0x280 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+0xc54/0xca0 kernel/hung_task.c:295 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 2965 Comm: systemd-journal Not tainted 5.15.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:mark_lock+0x147/0x1e00 kernel/locking/lockdep.c:4565 Code: 8a 04 38 84 c0 0f 85 41 10 00 00 8a 43 02 24 03 3c 01 ba 09 00 00 00 83 da 00 41 bd 01 00 00 00 48 89 d0 48 89 54 24 10 89 d1 <41> d3 e5 48 89 74 24 38 48 8d 5e 20 48 89 d8 48 c1 e8 03 48 89 44 RSP: 0018:ffffc900025af1a0 EFLAGS: 00000097 RAX: 0000000000000002 RBX: ffff88807b45d580 RCX: 0000000000000002 RDX: 0000000000000002 RSI: ffff88807b45dfa0 RDI: ffff88807b45d580 RBP: ffffc900025af390 R08: dffffc0000000000 R09: fffffbfff1fa31c1 R10: fffffbfff1fa31c1 R11: 0000000000000000 R12: 1ffff920004b5e40 R13: 0000000000000001 R14: ffff88807b45d580 R15: dffffc0000000000 FS: 00007fccae1078c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fccab707000 CR3: 000000007b2fc000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_usage kernel/locking/lockdep.c:4502 [inline] __lock_acquire+0xccf/0x2b00 kernel/locking/lockdep.c:4969 lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:363 [inline] lockref_get_not_dead+0x22/0xb0 lib/lockref.c:211 __legitimize_path fs/namei.c:698 [inline] legitimize_path fs/namei.c:708 [inline] legitimize_root fs/namei.c:743 [inline] try_to_unlazy+0x537/0xce0 fs/namei.c:779 may_lookup fs/namei.c:1684 [inline] link_path_walk+0x298/0xd00 fs/namei.c:2239 path_openat+0x25b/0x3670 fs/namei.c:3557 do_filp_open+0x277/0x4f0 fs/namei.c:3588 do_sys_openat2+0x13b/0x500 fs/open.c:1200 do_sys_open fs/open.c:1216 [inline] __do_sys_open fs/open.c:1224 [inline] __se_sys_open fs/open.c:1220 [inline] __x64_sys_open+0x221/0x270 fs/open.c:1220 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fccad696840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007ffefa085f98 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffefa0862a0 RCX: 00007fccad696840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000555fac8065d0 RBP: 000000000000000d R08: 000000000000c0ff R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000555fac7f9040 R14: 00007ffefa086260 R15: 0000555fac806670 ---------------- Code disassembly (best guess): 0: 8a 04 38 mov (%rax,%rdi,1),%al 3: 84 c0 test %al,%al 5: 0f 85 41 10 00 00 jne 0x104c b: 8a 43 02 mov 0x2(%rbx),%al e: 24 03 and $0x3,%al 10: 3c 01 cmp $0x1,%al 12: ba 09 00 00 00 mov $0x9,%edx 17: 83 da 00 sbb $0x0,%edx 1a: 41 bd 01 00 00 00 mov $0x1,%r13d 20: 48 89 d0 mov %rdx,%rax 23: 48 89 54 24 10 mov %rdx,0x10(%rsp) 28: 89 d1 mov %edx,%ecx * 2a: 41 d3 e5 shl %cl,%r13d <-- trapping instruction 2d: 48 89 74 24 38 mov %rsi,0x38(%rsp) 32: 48 8d 5e 20 lea 0x20(%rsi),%rbx 36: 48 89 d8 mov %rbx,%rax 39: 48 c1 e8 03 shr $0x3,%rax 3d: 48 rex.W 3e: 89 .byte 0x89 3f: 44 rex.R