INFO: task kworker/u8:0:12 blocked in I/O wait for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:23704 pid:12 tgid:12 ppid:2 task_flags:0x4248060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x1259/0x6920 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0xdd/0x2c0 kernel/sched/core.c:7376 io_schedule+0x8a/0xf0 kernel/sched/core.c:8220 rq_qos_wait+0x22d/0x330 block/blk-rq-qos.c:307 __wbt_wait block/blk-wbt.c:598 [inline] wbt_wait+0x18a/0x310 block/blk-wbt.c:658 __rq_qos_throttle+0x56/0xa0 block/blk-rq-qos.c:66 rq_qos_throttle block/blk-rq-qos.h:164 [inline] rq_qos_throttle block/blk-rq-qos.h:160 [inline] blk_mq_get_new_requests block/blk-mq.c:3032 [inline] blk_mq_submit_bio+0xc03/0x3000 block/blk-mq.c:3170 __submit_bio+0x90/0x3d0 block/blk-core.c:673 __submit_bio_noacct_mq block/blk-core.c:756 [inline] submit_bio_noacct_nocheck+0x549/0xc00 block/blk-core.c:790 submit_bio_noacct+0xc93/0x2130 block/blk-core.c:925 blk_crypto_submit_bio include/linux/blk-crypto.h:212 [inline] ext4_io_submit+0xf7/0x1a0 fs/ext4/page-io.c:396 io_submit_add_bh fs/ext4/page-io.c:452 [inline] ext4_bio_write_folio+0x709/0x1ab0 fs/ext4/page-io.c:547 mpage_process_page_bufs+0x473/0x8b0 fs/ext4/inode.c:2201 mpage_prepare_extent_to_map+0xb7f/0x1a20 fs/ext4/inode.c:2743 ext4_do_writepages+0x9bc/0x3e80 fs/ext4/inode.c:2884 ext4_writepages+0x34a/0x750 fs/ext4/inode.c:3032 do_writepages+0x278/0x600 mm/page-writeback.c:2560 __writeback_single_inode+0x164/0x1560 fs/fs-writeback.c:1803 writeback_sb_inodes+0x766/0x1c50 fs/fs-writeback.c:2114 __writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2190 wb_writeback+0x6f6/0xb50 fs/fs-writeback.c:2301 wb_check_old_data_flush fs/fs-writeback.c:2405 [inline] wb_do_writeback fs/fs-writeback.c:2484 [inline] wb_workfn+0x93f/0xc80 fs/fs-writeback.c:2512 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396 process_scheduled_works kernel/workqueue.c:3479 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560 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 INFO: task jbd2/sda1-8:4928 blocked in I/O wait for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jbd2/sda1-8 state:D stack:25832 pid:4928 tgid:4928 ppid:2 task_flags:0x240040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x1259/0x6920 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0xdd/0x2c0 kernel/sched/core.c:7376 io_schedule+0x8a/0xf0 kernel/sched/core.c:8220 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:258 __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:106 [inline] __wait_on_buffer+0x64/0x70 fs/buffer.c:118 wait_on_buffer include/linux/buffer_head.h:418 [inline] jbd2_journal_commit_transaction+0x37ef/0x6700 fs/jbd2/commit.c:834 kjournald2+0x200/0x760 fs/jbd2/journal.c:200 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/u8:0/12: 4, on CPU#0: #0: ffff8880212d7940 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371 #1: ffffc90000117d08 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372 #2: ffff888037f6e0e8 (&type->s_umount_key#57){++++}-{4:4}, at: super_trylock_shared+0x21/0xf0 fs/super.c:670 #3: ffff888037f6cc98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x278/0x600 mm/page-writeback.c:2560 locks held by khungtaskd/32: 1, last CPU#0: #0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6871 locks held by getty/5354: 2, on CPU#1: #0: ffff888033fc20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900032262e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 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