INFO: task kworker/0:9:10317 blocked for more than 143 seconds. Not tainted 6.13.0-syzkaller-09030-g6d61a53dd6f5 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:9 state:D stack:21696 pid:10317 tgid:10317 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events console_callback Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x113d/0x35d0 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75 ___down_common+0x2d7/0x460 kernel/locking/semaphore.c:225 __down_common kernel/locking/semaphore.c:246 [inline] __down+0x20/0x30 kernel/locking/semaphore.c:254 down+0x74/0xa0 kernel/locking/semaphore.c:63 console_lock+0x5b/0xa0 kernel/printk/printk.c:2833 console_callback+0x63/0x4c0 drivers/tty/vt/vt.c:3120 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff88ebf740 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] ffffffff88ebf740 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] ffffffff88ebf740 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 2 locks held by getty/2901: #0: ffff8881121410a0 (&tty->ldisc_sem){++++}-{0:0} , at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 ( &ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 3 locks held by syz-executor/2947: 4 locks held by udevd/5218: #0: ffff888139ded418 ( &p->lock){+.+.}-{4:4}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff88811a53ec88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff88810ffd8f08 (kn->active#4){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88810fb3f190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88810fb3f190 (&dev->mutex){....}-{4:4}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2729 4 locks held by udevd/5235: #0: ffff8881323ed540 ( &p->lock ){+.+.}-{4:4} , at: raw_spin_rq_lock_nested kernel/sched/core.c:598 [inline] , at: raw_spin_rq_lock kernel/sched/sched.h:1521 [inline] , at: rq_lock kernel/sched/sched.h:1852 [inline] , at: __schedule+0x28d/0x35d0 kernel/sched/core.c:6687 #1: ffff88813367d558 ( &ep->lock ){....}-{3:3} , at: ep_done_scan+0x2e/0x590 fs/eventpoll.c:754 #2: ffff888115344d58 (&ep->lock){....}-{3:3}, at: ep_poll_callback+0xd0/0xc80 fs/eventpoll.c:1347 #3: ffff8881110d06b0 (&lockref->lock){+.+.}-{3:3} , at: spin_lock include/linux/spinlock.h:351 [inline] , at: fast_dput fs/dcache.c:783 [inline] , at: dput.part.0+0x766/0x9b0 fs/dcache.c:861 3 locks held by kworker/0:6/5398: 3 locks held by syz-executor/6680: 2 locks held by kworker/0:9/10317: #0: ffff888100080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc900018c7d18 (console_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 5 locks held by kworker/1:10/11311: 3 locks held by kworker/0:10/11363: 5 locks held by kworker/1:12/11417: 4 locks held by kworker/0:11/11434: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-09030-g6d61a53dd6f5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.13.0-syzkaller-09030-g6d61a53dd6f5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events dvb_usb_read_remote_control RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x8/0x20 kernel/kcov.c:300 Code: bf 06 00 00 00 e9 b8 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 <40> 0f b6 d6 40 0f b6 f7 bf 01 00 00 00 e9 86 fe ff ff 66 0f 1f 44 RSP: 0018:ffffc9000009f3d0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000400 RCX: ffffffff8714e3bb RDX: ffff888101698000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000009f4b8 R08: 0000000000000001 R09: fffff52000013ed8 R10: ffffc9000009f6c5 R11: 0000000039373754 R12: 0000000000000000 R13: 000000007ffffff8 R14: 0000000000000400 R15: ffffffff8728dba5 FS: 0000000000000000(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9a94d07bac CR3: 000000011a0ee000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vsnprintf+0x29b/0x1180 lib/vsprintf.c:2783 sprintf+0xcd/0x110 lib/vsprintf.c:3006 print_caller kernel/printk/printk.c:1392 [inline] info_print_prefix+0x147/0x350 kernel/printk/printk.c:1409 record_print_text+0x141/0x400 kernel/printk/printk.c:1456 printk_get_next_message+0x2be/0x690 kernel/printk/printk.c:3008 console_emit_next_record kernel/printk/printk.c:3076 [inline] console_flush_all+0x6ec/0xc60 kernel/printk/printk.c:3210 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0xd9/0x210 kernel/printk/printk.c:3309 vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2432 _printk+0xc8/0x100 kernel/printk/printk.c:2457 dvb_usb_read_remote_control+0x174/0x1c0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:263 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244