INFO: task kworker/0:5:5705 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:5 state:D stack:22168 pid:5705 tgid:5705 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events console_callback Call Trace: context_switch kernel/sched/core.c:5520 [inline] __schedule+0x1259/0x6920 kernel/sched/core.c:7270 __schedule_loop kernel/sched/core.c:7347 [inline] schedule+0xdd/0x2c0 kernel/sched/core.c:7362 schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75 ___down_common kernel/locking/semaphore.c:293 [inline] __down_common+0x371/0x8b0 kernel/locking/semaphore.c:318 down+0x74/0xa0 kernel/locking/semaphore.c:100 console_lock+0x5b/0xa0 kernel/printk/printk.c:2896 class_console_lock_constructor include/linux/console.h:734 [inline] console_callback+0x62/0x4c0 drivers/tty/vt/vt.c:3352 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3387 process_scheduled_works kernel/workqueue.c:3470 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3551 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: locks held by kworker/0:0H/11: 2, last CPU#0: #0: ffff88801c056d40 ((wq_completion)events_highpri){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3362 #1: ffffc90000107d08 ((work_completion)(&vmidi->output_work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3363 locks held by khungtaskd/30: 1, last CPU#0: #0: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6793 locks held by getty/5349: 2, on CPU#1: #0: ffff8880371f30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211 locks held by kworker/0:5/5705: 2, on CPU#0: #0: ffff88801c057140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3362 #1: ffffc900044c7d08 (console_work){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3363 locks held by kworker/u8:14/5889: 3, last CPU#0: #0: ffff88801c08c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3362 #1: ffffc90004dffd08 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3363 #2: ffff88807a092258 (&devlink->lock_key#12){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x56/0xd20 drivers/net/netdevsim/dev.c:834 locks held by kworker/u8:15/5942: 3, last CPU#0: #0: ffff88801c08c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3362 #1: ffffc9000507fd08 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3363 #2: ffff88807ada3258 (&devlink->lock_key#4){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x56/0xd20 drivers/net/netdevsim/dev.c:834 locks held by kworker/u8:16/9971: 3, last CPU#0: #0: ffff888033e34940 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3362 #1: ffffc900060afd08 ((work_completion)(&(&bat_priv->mcast.work)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3363 #2: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #2: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #2: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1183 [inline] #2: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495 locks held by kworker/u8:20/9975: 3, last CPU#0: #0: ffff88801c08c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3362 #1: ffffc9000614fd08 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3363 #2: ffff8880582f0258 (&devlink->lock_key#3){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x56/0xd20 drivers/net/netdevsim/dev.c:834 locks held by syz.2.1060/10604: 3, last CPU#0: #0: ffff888038601cc0 (&ima_iint_mutex_key[depth]#2){+.+.}-{4:4}, at: process_measurement+0x5ab/0x2350 security/integrity/ima/ima_main.c:319 #1: ffffffff8f0bc0f0 (kclist_lock){++++}-{0:0}, at: proc_reg_read_iter+0x11b/0x310 fs/proc/inode.c:295 #2: ffffffff8ef7b588 (page_offline_rwsem){.+.+}-{4:4}, at: read_kcore_iter+0x1f8/0x1800 fs/proc/kcore.c:343 locks held by syz.6.1674/13252: 6, last CPU#0: #0: ffff88802c8690a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffff88802c869128 (&tty->atomic_write_lock){+.+.}-{4:4}, at: tty_write_lock drivers/tty/tty_io.c:939 [inline] #1: ffff88802c869128 (&tty->atomic_write_lock){+.+.}-{4:4}, at: iterate_tty_write drivers/tty/tty_io.c:958 [inline] #1: ffff88802c869128 (&tty->atomic_write_lock){+.+.}-{4:4}, at: file_tty_write.isra.0+0x24b/0x890 drivers/tty/tty_io.c:1054 #2: ffff88802c8692c8 (&tty->termios_rwsem){++++}-{4:4}, at: class_rwsem_read_constructor include/linux/rwsem.h:259 [inline] #2: ffff88802c8692c8 (&tty->termios_rwsem){++++}-{4:4}, at: n_tty_write+0x1b8/0x1160 drivers/tty/n_tty.c:2349 #3: ffffc90007996370 (&ldata->output_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #3: ffffc90007996370 (&ldata->output_lock){+.+.}-{4:4}, at: process_output_block drivers/tty/n_tty.c:513 [inline] #3: ffffc90007996370 (&ldata->output_lock){+.+.}-{4:4}, at: n_tty_write+0x54c/0x1160 drivers/tty/n_tty.c:2366 #4: ffffffff8edd6040 (console_lock){+.+.}-{0:0}, at: class_console_lock_constructor include/linux/console.h:734 [inline] #4: ffffffff8edd6040 (console_lock){+.+.}-{0:0}, at: do_con_write+0x15b/0x4980 drivers/tty/vt/vt.c:3290 #5: ffffffff8edd60b8 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:305 [inline] #5: ffffffff8edd60b8 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:428 [inline] #5: ffffffff8edd60b8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline] #5: ffffffff8edd60b8 (console_srcu){....}-{0:0}, at: console_flush_one_record+0xfd/0xf10 kernel/printk/printk.c:3246 locks held by syz.9.1835/13912: 2, on CPU#0: #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2010 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x425/0xe20 drivers/tty/tty_io.c:2093 #1: ffff8880758181b0 (&tty->legacy_mutex){+.+.}-{4:4}, at: tty_init_dev.part.0+0x39/0x470 drivers/tty/tty_io.c:1379 locks held by syz.7.1839/13958: 1, on CPU#0: #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2010 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x425/0xe20 drivers/tty/tty_io.c:2093 locks held by syz.8.1890/14271: 1, on CPU#0: #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: ptmx_open drivers/tty/pty.c:800 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: ptmx_open+0x11a/0x360 drivers/tty/pty.c:767 locks held by syz.0.1911/14466: 1, on CPU#0: #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2010 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x425/0xe20 drivers/tty/tty_io.c:2093 locks held by syz.2.1970/14992: 1, on CPU#0: #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2010 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x425/0xe20 drivers/tty/tty_io.c:2093 locks held by syz.5.1982/15094: 1, on CPU#0: #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: ptmx_open drivers/tty/pty.c:800 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: ptmx_open+0x11a/0x360 drivers/tty/pty.c:767 locks held by syz.4.2029/15497: 1, on CPU#0: #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2010 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x425/0xe20 drivers/tty/tty_io.c:2093 locks held by syz.1.2043/15586: 1, on CPU#0: #0: ffff88807b5ca480 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_check_last_writer security/integrity/ima/ima_main.c:215 [inline] #0: ffff88807b5ca480 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_file_free+0x146/0x340 security/integrity/ima/ima_main.c:251 locks held by syz.1.2043/15589: 1, on CPU#0: #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2010 [inline] #0: ffffffff8fba5280 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x425/0xe20 drivers/tty/tty_io.c:2093 locks held by syz.1.2043/15593: 2, last CPU#0: #0: ffff888037522460 (sb_writers#6){.+.+}-{0:0}, at: do_open fs/namei.c:4830 [inline] #0: ffff888037522460 (sb_writers#6){.+.+}-{0:0}, at: path_openat+0x1a45/0x2440 fs/namei.c:5000 #1: ffff88807b5ca480 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x5ab/0x2350 security/integrity/ima/ima_main.c:319 locks held by syz.6.2051/15608: 2, last CPU#0: #0: ffff88807d5bc378 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline] #0: ffff88807d5bc378 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x124/0xa00 mm/mmap.c:1299 #1: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #1: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #1: ffffffff8ede9c80 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x310 mm/pgtable-generic.c:290 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:123 nmi_trigger_cpumask_backtrace+0x21f/0x2a0 lib/nmi_backtrace.c:66 trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xcb1/0x1030 kernel/hung_task.c:561 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245