INFO: task kworker/1:1:51 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/1:1 state:D stack:21776 pid:51 tgid:51 ppid:2 flags:0x00004000 Workqueue: events console_callback Call Trace: 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 Showing all locks held in the system: 5 locks held by kworker/0:0/8: #0: ffff888106aabd48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000008fd80 ((work_completion)(&hub->events) ){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff888108bf6190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] ffff888108bf6190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5851 #3: ffff88811bc1b190 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:1014 [inline] , at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff8881116c8160 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:1014 [inline] , at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 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 kworker/1:1/51: #0: ffff888100080948 ((wq_completion)events ){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90000527d80 (console_work){+.+.}-{0:0} , at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 2 locks held by kworker/u8:4/55: 2 locks held by getty/2904: #0: ffff88811262a0a0 (&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 kworker/1:4/5235: #0: ffff888106aabd48 ((wq_completion)usb_hub_wq ){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc9000200fd80 ((work_completion)(&hub->events) ){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff88810b349190 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:1014 [inline] , at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5851 6 locks held by kworker/0:4/5244: 4 locks held by udevd/5248: #0: ffff888118aa19e0 (&p->lock ){+.+.}-{4:4}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff888120f9ac88 (&of->mutex #2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff88810afa0e18 (kn->active#3){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88810b349190 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] ){....}-{4:4}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2729 3 locks held by kworker/0:5/5292: #0: ffff888106aabd48 ( (wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90002267d80 ((work_completion)(&hub->events)){+.+.}-{0:0} , at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff88810ab9d190 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:1014 [inline] , at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5851 4 locks held by kworker/0:7/5579: 4 locks held by udevd/6390: #0: ffff888108fcc1c8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff88810fad2488 (&of->mutex #2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff8881139f5a58 (kn->active #3){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88811bc1b190 (&dev->mutex ){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] ){....}-{4:4}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2729 2 locks held by kworker/0:9/6482: 2 locks held by kworker/u8:0/7419: 1 lock held by syz.2.1288/9599: ============================================= NMI backtrace for cpu 1 CPU: 1 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: __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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6482 Comm: kworker/0:9 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 legacy_dvb_usb_read_remote_control RIP: 0010:lock_acquire+0x29/0xb0 kernel/locking/lockdep.c:5820 Code: 90 f3 0f 1e fa 41 57 4d 89 cf 41 56 45 89 c6 41 55 41 89 cd 41 54 41 89 d4 55 89 f5 53 48 83 ec 08 48 8b 5c 24 40 48 89 3c 24 <53> e8 51 10 ff ff 48 c7 c0 14 28 56 8a 48 ba 00 00 00 00 00 fc ff RSP: 0018:ffffc900000079c0 EFLAGS: 00000086 RAX: 0000000000000104 RBX: ffffffff825ee669 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff935d3180 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000004 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe7fe97c78 CR3: 000000011f982000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 debug_object_activate+0x149/0x4a0 lib/debugobjects.c:818 debug_hrtimer_activate kernel/time/hrtimer.c:428 [inline] debug_activate kernel/time/hrtimer.c:469 [inline] enqueue_hrtimer+0x25/0x3c0 kernel/time/hrtimer.c:1076 __hrtimer_start_range_ns kernel/time/hrtimer.c:1251 [inline] hrtimer_start_range_ns+0x800/0xc60 kernel/time/hrtimer.c:1293 hrtimer_start include/linux/hrtimer.h:260 [inline] dummy_timer+0x290a/0x3960 drivers/usb/gadget/udc/dummy_hcd.c:2007 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1820 handle_softirqs+0x206/0x8d0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1049 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 0a 21 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc90014647a30 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000017 RCX: ffffffff813b49de RDX: ffff888102b73a80 RSI: ffffffff813b49e8 RDI: 0000000000000007 RBP: 1ffff920028c8f48 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000200 R14: ffff888102ab9d40 R15: ffffc90014647b18 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_query+0x496/0x770 drivers/media/usb/dvb-usb/m920x.c:193 legacy_dvb_usb_read_remote_control+0x10a/0x500 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123 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