INFO: task jbd2/sda1-8:2813 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jbd2/sda1-8 state:D stack:25912 pid:2813 tgid:2813 ppid:2 task_flags:0x240040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0xeb1/0x4220 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7008 io_schedule+0x8a/0xf0 kernel/sched/core.c:7835 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:105 [inline] __wait_on_buffer+0x64/0x70 fs/buffer.c:124 wait_on_buffer include/linux/buffer_head.h:420 [inline] journal_wait_on_commit_record fs/jbd2/commit.c:171 [inline] jbd2_journal_commit_transaction+0x49a6/0x6900 fs/jbd2/commit.c:881 kjournald2+0x200/0x760 fs/jbd2/journal.c:201 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x6c3/0xcb0 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: 2 locks held by kworker/1:0/23: 1 lock held by khungtaskd/30: #0: ffffffff896de760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff896de760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff896de760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 1 lock held by klogd/2841: #0: ffff8881f56396a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline] (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1618 [inline] (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1949 [inline] (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x2ca/0x4220 kernel/sched/core.c:6814 2 locks held by getty/2916: #0: ffff8881158b90a0 (&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+0x419/0x1500 drivers/tty/n_tty.c:2211 6 locks held by kworker/1:4/5228: 6 locks held by kworker/0:5/5252: 6 locks held by kworker/1:5/5297: 3 locks held by kworker/0:6/5683: 2 locks held by kworker/u8:3/6906: #0: ffff8881000ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc90014a7fd18 ((work_completion)(&pool->idle_cull_work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 4 locks held by udevd/13519: 7 locks held by kworker/1:6/13739: #0: ffff88810228b148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251 #1: ffffc90001f3fd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252 #2: ffff88810bb801e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #2: ffff88810bb801e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88811031e1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #3: ffff88811031e1e0 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336 #4: ffff8881056eb1a8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline] #4: ffff8881056eb1a8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1166 [inline] #4: ffff8881056eb1a8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1364 #5: ffffffff8a50be68 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #5: ffffffff8a50be68 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x184/0x4d0 drivers/input/input.c:2187 #6: ffffffff896ea2b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311 2 locks held by kworker/1:8/14102: 2 locks held by kworker/u8:1/16184: 2 locks held by kworker/u8:0/19335: 2 locks held by kworker/u8:2/20497: 2 locks held by kworker/u8:4/20522: 1 lock held by syz-executor/21506: #0: ffffffff896ea2b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [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:346 [inline] watchdog+0xd25/0x1050 kernel/hung_task.c:515 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5225 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: events legacy_dvb_usb_read_remote_control RIP: 0010:vsnprintf+0x422/0x1240 lib/vsprintf.c:2887 Code: ff df 48 c1 ea 03 80 3c 02 00 0f 85 13 0d 00 00 49 8b 16 48 8b 8c 24 80 00 00 00 48 8b 74 24 28 48 8b 7c 24 40 e8 be 56 ff ff <48> 89 da 48 c1 ea 03 48 89 44 24 40 48 b8 00 00 00 00 00 fc ff df RSP: 0018:ffffc9000317f2f0 EFLAGS: 00000287 RAX: ffffc9000317f5fd RBX: ffffffff878ab4a4 RCX: 1ffff9200062fe4b RDX: ffff8881191c5880 RSI: ffffffff8766add1 RDI: ffffc9000317f5fa RBP: ffffc9000317f3e0 R08: 0000000000000001 R09: 0000000000000007 R10: ffffc9000317f5f7 R11: 0000000000543354 R12: 0000000000000005 R13: 0000000000000018 R14: ffffc9000317f480 R15: ffffc9000317f410 FS: 0000000000000000(0000) GS:ffff8882687c9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f70b5ca8060 CR3: 0000000129a02000 CR4: 00000000003506f0 Call Trace: sprintf+0xcc/0x100 lib/vsprintf.c:3111 print_caller kernel/printk/printk.c:1370 [inline] info_print_prefix+0x146/0x350 kernel/printk/printk.c:1387 record_print_text+0x143/0x3c0 kernel/printk/printk.c:1434 printk_get_next_message+0x2d1/0x6c0 kernel/printk/printk.c:3072 console_emit_next_record kernel/printk/printk.c:3137 [inline] console_flush_one_record+0x67c/0xe50 kernel/printk/printk.c:3269 console_flush_all kernel/printk/printk.c:3343 [inline] __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3413 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479 _printk+0xcf/0x110 kernel/printk/printk.c:2504 legacy_dvb_usb_read_remote_control.cold+0x11/0x16 drivers/media/usb/dvb-usb/dvb-usb-remote.c:124 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245