INFO: task kworker/u4:9:5244 blocked for more than 143 seconds. Not tainted 6.2.0-rc7-next-20230207-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:9 state:D stack:26416 pid:5244 ppid:2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:5301 [inline] __schedule+0x245a/0x5a60 kernel/sched/core.c:6619 schedule+0xde/0x1a0 kernel/sched/core.c:6695 schedule_timeout+0x276/0x2b0 kernel/time/timer.c:2143 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common+0x1ce/0x5c0 kernel/sched/completion.c:106 io_ring_exit_work+0x521/0x1370 io_uring/io_uring.c:3027 process_one_work+0x9bf/0x1820 kernel/workqueue.c:2390 worker_thread+0x669/0x1090 kernel/workqueue.c:2537 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Showing all locks held in the system: 2 locks held by kworker/u4:1/12: #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x86d/0x1820 kernel/workqueue.c:2361 #1: ffffc90000117da8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1820 kernel/workqueue.c:2365 1 lock held by rcu_tasks_kthre/13: #0: ffffffff8c794230 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/14: #0: ffffffff8c793f30 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/28: #0: ffffffff8c794e00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x390 kernel/locking/lockdep.c:6545 2 locks held by kworker/u4:2/41: 2 locks held by getty/4761: #0: ffff88814a65e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc900015b02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2177 2 locks held by kworker/u4:9/5244: #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x86d/0x1820 kernel/workqueue.c:2361 #1: ffffc90004c07da8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1820 kernel/workqueue.c:2365 1 lock held by syz-executor.5/5596: 1 lock held by syz-executor.3/5641: 1 lock held by syz-executor.4/5651: 1 lock held by syz-executor.1/5765: 1 lock held by syz-executor.3/5822: 1 lock held by syz-executor.0/5832: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.2.0-rc7-next-20230207-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 nmi_cpu_backtrace+0x316/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x3a7/0x460 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xe94/0x11e0 kernel/hung_task.c:379 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5263 Comm: kworker/u4:12 Not tainted 6.2.0-rc7-next-20230207-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Workqueue: phy29 ieee80211_iface_work RIP: 0010:rcu_lockdep_current_cpu_online kernel/rcu/tree.c:4077 [inline] RIP: 0010:rcu_lockdep_current_cpu_online+0x38/0x140 kernel/rcu/tree.c:4069 Code: 00 f0 00 b8 01 00 00 00 75 0a 8b 15 56 04 08 0d 85 d2 75 01 c3 55 53 65 ff 05 2c f7 95 7e e8 2f f7 a5 08 48 c7 c3 40 d1 03 00 <83> f8 07 89 c5 0f 87 e9 00 00 00 48 8d 3c ed c0 49 11 8c 48 b8 00 RSP: 0018:ffffc90004d7fa60 EFLAGS: 00000006 RAX: 0000000000000001 RBX: 000000000003d140 RCX: ffffffff8165233c RDX: 0000000000000001 RSI: 0000000000000003 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8e75c457 R10: fffffbfff1ceb88a R11: 0000000000094001 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff841d9f0b FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c01a575900 CR3: 0000000043d06000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:112 [inline] rcu_read_lock_held_common kernel/rcu/update.c:102 [inline] rcu_read_lock_sched_held+0x29/0x70 kernel/rcu/update.c:123 trace_lock_acquire+0x1f1/0x2b0 include/trace/events/lock.h:24 lock_acquire+0x32/0xc0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 __debug_check_no_obj_freed lib/debugobjects.c:984 [inline] debug_check_no_obj_freed+0xcb/0x420 lib/debugobjects.c:1027 slab_free_hook mm/slub.c:1756 [inline] slab_free_freelist_hook+0xeb/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] kmem_cache_free+0xec/0x4e0 mm/slub.c:3809 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:873 __kfree_skb net/core/skbuff.c:930 [inline] kfree_skb_reason+0x127/0x1e0 net/core/skbuff.c:962 kfree_skb include/linux/skbuff.h:1213 [inline] ieee80211_iface_work+0x357/0xd70 net/mac80211/iface.c:1639 process_one_work+0x9bf/0x1820 kernel/workqueue.c:2390 worker_thread+0x669/0x1090 kernel/workqueue.c:2537 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308