INFO: task kworker/u4:10:3882 blocked for more than 144 seconds. Not tainted 5.15.106-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:10 state:D stack:26752 pid: 3882 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:5026 [inline] __schedule+0x12c4/0x4590 kernel/sched/core.c:6372 schedule+0x11b/0x1f0 kernel/sched/core.c:6455 schedule_timeout+0xac/0x300 kernel/time/timer.c:1860 do_wait_for_common+0x2d9/0x480 kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x48/0x60 kernel/sched/completion.c:138 io_ring_exit_work+0x6a9/0x1330 io_uring/io_uring.c:9711 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2306 worker_thread+0xaca/0x1280 kernel/workqueue.c:2453 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c91b920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/1:2/1065: #0: ffff888011c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc90004847d20 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 #2: ffffffff8c91fd70 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:3994 3 locks held by kworker/0:2/1281: #0: ffff888011c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc9000536fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 #2: ffffffff8c91fe68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #2: ffffffff8c91fe68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:840 2 locks held by getty/3267: #0: ffff8880240c7098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002bb32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1da0 drivers/tty/n_tty.c:2147 2 locks held by kworker/u4:10/3882: #0: ffff888011c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc90004777d20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 5 locks held by syz-executor.3/3958: 1 lock held by syz-executor.3/4101: #0: ffffffff8c91fe68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #0: ffffffff8c91fe68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:840 4 locks held by kworker/u4:12/4236: #0: ffff888011db5138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc90002d0fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 #2: ffffffff8d9c7d90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:558 #3: ffffffff8c91fd70 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:3994 2 locks held by kworker/0:14/4529: #0: ffff888011c66538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc900046b7d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 2 locks held by syz-executor.0/5245: #0: ffffffff8d9c7d90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x37b/0x5d0 net/core/net_namespace.c:469 #1: ffffffff8c91fd70 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:3994 1 lock held by syz-executor.2/5235: 1 lock held by dhcpcd/5271: #0: ffff888069d1e120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1649 [inline] #0: ffff888069d1e120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2a/0xc90 net/packet/af_packet.c:3159 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3958 Comm: syz-executor.3 Not tainted 5.15.106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023 RIP: 0010:check_preemption_disabled+0xb/0x110 lib/smp_processor_id.c:13 Code: 01 00 00 65 ff 0d c1 4c ec 75 5b c3 cc cc cc 48 c7 c7 e0 50 d8 8a 48 c7 c6 20 51 d8 8a eb 00 41 57 41 56 41 54 53 48 83 ec 10 <65> 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 8b 1d 10 1a eb 75 65 RSP: 0018:ffffc90004b6f0c8 EFLAGS: 00000082 RAX: 0000000000000001 RBX: ffffc90004b6f160 RCX: ffffffff8162f0a2 RDX: dffffc0000000000 RSI: ffffffff8a8b0380 RDI: ffffffff8ad85140 RBP: ffffc90004b6f248 R08: dffffc0000000000 R09: fffffbfff1f76e36 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200096de28 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000046 FS: 00007fc624ee7700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6b8092e058 CR3: 00000000749ca000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:436 [inline] lock_acquire+0x1eb/0x4f0 kernel/locking/lockdep.c:5624 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 prepare_to_wait_event+0x26/0x3e0 kernel/sched/wait.c:307 p9_client_rpc+0x39a/0x1290 net/9p/client.c:760 p9_client_flush+0x277/0x570 net/9p/client.c:668 p9_client_rpc+0xb35/0x1290 net/9p/client.c:784 p9_client_create+0x9b4/0x1000 net/9p/client.c:1052 v9fs_session_init+0x1fe/0x1910 fs/9p/v9fs.c:409 v9fs_mount+0x72/0x860 fs/9p/vfs_super.c:126 legacy_get_tree+0xeb/0x180 fs/fs_context.c:610 vfs_get_tree+0x88/0x270 fs/super.c:1508 do_new_mount+0x28b/0xad0 fs/namespace.c:2994 do_mount fs/namespace.c:3337 [inline] __do_sys_mount fs/namespace.c:3545 [inline] __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3522 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fc626975169 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc624ee7168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fc626a94f80 RCX: 00007fc626975169 RDX: 0000000020000280 RSI: 00000000200002c0 RDI: 0000000000000000 RBP: 00007fc6269d0ca1 R08: 0000000020000200 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd945e4abf R14: 00007fc624ee7300 R15: 0000000000022000