INFO: task kworker/0:10:18368 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/0:10 state:D stack:22392 pid:18368 tgid:18368 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 khungtaskd/31: 1, last CPU#0: #0: ffffffff8ede9de0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8ede9de0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8ede9de0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6793 locks held by getty/5355: 2, on CPU#1: #0: ffff8880336080a0 (&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/u8:56/14112: 6, on CPU#0: #0: ffff88801c08c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3362 #1: ffffc900036bfd08 ((work_completion)(&buf->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3363 #2: ffff88801c0aa0b8 (&buf->lock){+.+.}-{4:4}, at: flush_to_ldisc+0x34/0x730 drivers/tty/tty_buffer.c:474 #3: ffff8880360210a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x21/0x90 drivers/tty/tty_ldisc.c:263 #4: ffff8880360212c8 (&tty->termios_rwsem){++++}-{4:4}, at: class_rwsem_read_constructor include/linux/rwsem.h:259 [inline] #4: ffff8880360212c8 (&tty->termios_rwsem){++++}-{4:4}, at: n_tty_receive_buf_common+0x85/0x1930 drivers/tty/n_tty.c:1678 #5: ffffc90003feb370 (&ldata->output_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #5: ffffc90003feb370 (&ldata->output_lock){+.+.}-{4:4}, at: flush_echoes drivers/tty/n_tty.c:783 [inline] #5: ffffc90003feb370 (&ldata->output_lock){+.+.}-{4:4}, at: __receive_buf drivers/tty/n_tty.c:1618 [inline] #5: ffffc90003feb370 (&ldata->output_lock){+.+.}-{4:4}, at: n_tty_receive_buf_common+0x41b/0x1930 drivers/tty/n_tty.c:1715 locks held by kworker/0:10/18368: 2, on CPU#0: #0: ffff88801c057140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3362 #1: ffffc90003c0fd08 (console_work){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3363 locks held by syz.3.3790/20801: 2, last CPU#0: #0: ffffffff8edd6040 (console_lock){+.+.}-{0:0}, at: class_console_lock_constructor include/linux/console.h:734 [inline] #0: ffffffff8edd6040 (console_lock){+.+.}-{0:0}, at: vt_disallocate drivers/tty/vt/vt_ioctl.c:632 [inline] #0: ffffffff8edd6040 (console_lock){+.+.}-{0:0}, at: vt_ioctl+0x19e5/0x3150 drivers/tty/vt/vt_ioctl.c:893 #1: ffffffff8edd60b8 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline] #1: ffffffff8edd60b8 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline] #1: ffffffff8edd60b8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline] #1: ffffffff8edd60b8 (console_srcu){....}-{0:0}, at: console_flush_one_record+0xfd/0xf10 kernel/printk/printk.c:3246 locks held by syz.8.4274/23421: 1, on CPU#0: #0: ffff88809c2db798 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_check_last_writer security/integrity/ima/ima_main.c:215 [inline] #0: ffff88809c2db798 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: ima_file_free+0x146/0x340 security/integrity/ima/ima_main.c:251 locks held by syz.8.4274/23425: 2, last CPU#0: #0: ffff88809c2db798 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x5ab/0x2350 security/integrity/ima/ima_main.c:319 #1: ffffffff8ede9de0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffffff8ede9de0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8ede9de0 (rcu_read_lock){....}-{1:3}, at: __update_page_owner_handle+0x63/0x530 mm/page_owner.c:273 locks held by syz.4.4275/23428: 1, on CPU#0: #0: ffff8880310bfa70 (&sig->exec_update_lock){++++}-{4:4}, at: landlock_restrict_sibling_threads+0x1c7/0x14c0 security/landlock/tsync.c:513 locks held by syz.4.4275/23447: 3, last CPU#0: #0: ffff8880328c7268 (&fc->uapi_mutex){+.+.}-{4:4}, at: __do_sys_fsconfig+0x4e1/0xcb0 fs/fsopen.c:461 #1: ffff88808a86e0e8 (&type->s_umount_key#98/1){+.+.}-{4:4}, at: alloc_super fs/super.c:365 [inline] #1: ffff88808a86e0e8 (&type->s_umount_key#98/1){+.+.}-{4:4}, at: sget_fc+0x3c2/0x1f20 fs/super.c:889 #2: ffff88807d8ac940 ((wq_completion)ceph-inode){+.+.}-{0:0}, at: touch_wq_lockdep_map+0x9c/0x1c0 kernel/workqueue.c:4102 locks held by syz.6.4277/23442: 1, last CPU#0: #0: ffffffff8fbe84c0 (reading_mutex){+.+.}-{4:4}, at: rng_dev_read+0xec/0x910 drivers/char/hw_random/core.c:254 locks held by syz.2.4279/23440: 2, last CPU#0: #0: ffffffff90cabc68 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:579 #1: ffffffff90cc4740 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:149 [inline] #1: ffffffff90cc4740 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x50 net/core/dev.c:11617 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 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