INFO: task kworker/0:0:8 blocked for more than 143 seconds. Not tainted 6.13.0-rc7-syzkaller-g70cd0576aa39 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:0 state:D stack:20736 pid:8 tgid:8 ppid:2 flags:0x00004000 Workqueue: events console_callback Call Trace: <TASK> context_switch kernel/sched/core.c:5369 [inline] __schedule+0x102c/0x34b0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 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+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Showing all locks held in the system: 2 locks held by kworker/0:0/8: #0: ffff888100080948 ((wq_completion)events){+.+.}-{0:0} , at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000008fd80 (console_work ){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 1 lock held by khungtaskd/30: #0: ffffffff88ebc880 ( rcu_read_lock){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] , at: rcu_read_lock include/linux/rcupdate.h:849 [inline] , at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6744 2 locks held by getty/2904: #0: ffff88811219f0a0 ( &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 4 locks held by udevd/5198: #0: ffff88813d745e80 (&p->lock ){+.+.}-{4:4}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff88811d697488 ( &of->mutex ){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff8881077ed5a8 (kn->active ){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88810af84190 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:1014 [inline] , at: uevent_show+0x188/0x3b0 drivers/base/core.c:2729 5 locks held by kworker/1:5/5234: 6 locks held by kworker/0:3/5283: 4 locks held by udevd/8853: #0: ffff88811d47ed58 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff88811f2b8c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888120850008 (kn->active){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88814010a190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88814010a190 (&dev->mutex){....}-{4:4}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2729 5 locks held by kworker/0:5/16306: 3 locks held by kworker/1:8/22930: #0: ffff888106689548 ((wq_completion)usb_hub_wq ){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90014e8fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff88810abd4190 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:1014 [inline] , at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5851 5 locks held by kworker/1:14/23675: #0: ffff888106689548 ((wq_completion)usb_hub_wq ){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000278fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff88810ab47190 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] ){....}-{4:4}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5851 #3: ffff88814010a190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88814010a190 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff8881375f5160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff8881375f5160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 1 lock held by syz.4.5151/24885: 1 lock held by dhcpcd-run-hook/24893: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc7-syzkaller-g70cd0576aa39 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: <TASK> __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:234 [inline] watchdog+0xf14/0x1240 kernel/hung_task.c:397 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 22933 Comm: kworker/1:9 Not tainted 6.13.0-rc7-syzkaller-g70cd0576aa39 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events dvb_usb_read_remote_control RIP: 0010:native_apic_mem_write+0xc/0x20 arch/x86/include/asm/apic.h:104 Code: 1f 00 b8 01 00 00 00 c3 cc cc cc cc 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 89 ff 89 b7 00 c0 5f ff <c3> cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 RSP: 0018:ffffc900001b8eb8 EFLAGS: 00000046 RAX: ffffffff8117abb0 RBX: ffff8881f5928300 RCX: 0000000000000020 RDX: 1ffff1103eb25061 RSI: 000000000001d4fd RDI: 0000000000000380 RBP: 000000000001d4fd R08: 0000000000000005 R09: 000000000000003f R10: 0000000000000020 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000020 R14: 0000000000000000 R15: 000002e2238c5947 FS: 0000000000000000(0000) GS:ffff8881f5900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9c23aa1000 CR3: 0000000121030000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <IRQ> apic_write arch/x86/include/asm/apic.h:405 [inline] lapic_next_event+0x10/0x20 arch/x86/kernel/apic/apic.c:415 clockevents_program_event+0x26f/0x380 kernel/time/clockevents.c:334 tick_program_event+0xa9/0x140 kernel/time/tick-oneshot.c:44 hrtimer_interrupt+0x3e4/0x8e0 kernel/time/hrtimer.c:1878 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x8b/0xb0 arch/x86/kernel/apic/apic.c:1049 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline] RIP: 0010:vprintk_emit+0x621/0x6f0 kernel/printk/printk.c:2431 Code: 85 ed 0f 85 81 00 00 00 e8 2c 21 20 00 9c 41 5c 41 81 e4 00 02 00 00 31 ff 4c 89 e6 e8 48 1c 20 00 4d 85 e4 0f 85 8d 00 00 00 <e8> 0a 21 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc90014d8fad8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000017 RCX: ffffffff813b49de RDX: ffff88813d30ba80 RSI: ffffffff813b49e8 RDI: 0000000000000007 RBP: 1ffff920029b1f5d R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000200 R14: ffff888102ad1d40 R15: ffffc90014d8fbc0 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:86 _printk+0xc8/0x100 kernel/printk/printk.c:2457 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_core_query+0x2d7/0x500 drivers/media/usb/dvb-usb/m920x.c:229 dvb_usb_read_remote_control+0xda/0x1c0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:261 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+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK>