INFO: task kworker/u4:4:953 blocked for more than 143 seconds. Not tainted 5.11.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:4 state:D stack:24496 pid: 953 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4313 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5064 schedule+0xcf/0x270 kernel/sched/core.c:5143 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1854 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x163/0x260 kernel/sched/completion.c:138 kthread_park+0x122/0x1b0 kernel/kthread.c:557 io_put_sq_data fs/io_uring.c:7306 [inline] io_sq_thread_stop+0x42a/0x570 fs/io_uring.c:7404 io_finish_async fs/io_uring.c:7411 [inline] io_ring_ctx_free fs/io_uring.c:8576 [inline] io_ring_exit_work+0xac/0x730 fs/io_uring.c:8668 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Showing all locks held in the system: 4 locks held by kworker/u4:1/22: 2 locks held by kworker/u4:4/953: #0: ffff888010071138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010071138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010071138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010071138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010071138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010071138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2246 #1: ffffc90004197da8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2250 1 lock held by khungtaskd/1646: #0: ffffffff8b363860 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8154: #0: ffff888022bfc430 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947 2 locks held by agetty/8390: #0: ffff8880288ef098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:266 #1: ffffc900010042e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x21d/0x1aa0 drivers/tty/n_tty.c:2158 3 locks held by kworker/1:3/8958: #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2246 #1: ffffc90001f67da8 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2250 #2: ffffffff8c948ba8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 3 locks held by kworker/1:6/10632: #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888010063d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2246 #1: ffffc90017e9fda8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2250 #2: ffffffff8c948ba8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:250 1 lock held by syz-executor.2/15938: #0: ffffffff8c948ba8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8c948ba8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5561 1 lock held by syz-executor.5/15969: #0: ffffffff8c948ba8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8c948ba8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5561 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1646 Comm: khungtaskd Not tainted 5.11.0-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:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd43/0xfa0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4885 Comm: systemd-journal Not tainted 5.11.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:mark_lock+0x2/0x1730 kernel/locking/lockdep.c:4372 Code: 0f 1f 84 00 00 00 00 00 be 00 00 01 00 48 c7 c7 80 34 57 8e e8 0f 3b 62 02 48 98 c3 66 90 66 2e 0f 1f 84 00 00 00 00 00 41 57 <41> 56 41 55 41 54 41 89 d4 48 ba 00 00 00 00 00 fc ff df 55 53 48 RSP: 0018:ffffc90001597cd0 EFLAGS: 00000046 RAX: ffffffff8ebebd80 RBX: 0000000000000000 RCX: 1ffff11002976db0 RDX: 0000000000000008 RSI: ffff888014bb6d88 RDI: ffff888014bb6400 RBP: ffff888014bb6400 R08: 0000000000000000 R09: ffffffff8ebe97a7 R10: fffffbfff1d7d2f4 R11: 0000000000000000 R12: ffff888014bb6d88 R13: 0000000000000002 R14: ffffffff8b363860 R15: 000000000000002d FS: 00007fd069e6b8c0(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd0672e9000 CR3: 0000000014240000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_usage kernel/locking/lockdep.c:4332 [inline] __lock_acquire+0x8bb/0x5500 kernel/locking/lockdep.c:4786 lock_acquire kernel/locking/lockdep.c:5437 [inline] lock_acquire+0x29d/0x740 kernel/locking/lockdep.c:5402 rcu_lock_acquire include/linux/rcupdate.h:253 [inline] rcu_read_lock include/linux/rcupdate.h:642 [inline] __task_pid_nr_ns+0x3d/0x4b0 kernel/pid.c:497 task_tgid_vnr include/linux/sched.h:1470 [inline] __do_sys_getpid+0x1a/0x20 kernel/sys.c:908 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fd069104f17 Code: ff ff ff 48 8b 4d a0 0f b7 51 fe 48 8b 4d a8 66 89 54 08 fe e9 1a ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 b8 27 00 00 00 0f 05 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00 RSP: 002b:00007ffff6846748 EFLAGS: 00000206 ORIG_RAX: 0000000000000027 RAX: ffffffffffffffda RBX: 0000557f59853200 RCX: 00007fd069104f17 RDX: 00007ffff6846800 RSI: 0000000000000000 RDI: 0000557f59853200 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000206 R12: 00007ffff6846800 R13: 0000000000001315 R14: 00007ffff68495f0 R15: 00007ffff6846c00