INFO: task kworker/u8:4:57 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/u8:4 state:D stack:24128 pid:57 tgid:57 ppid:2 task_flags:0x4248160 flags:0x00080000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 io_schedule+0x8a/0xf0 kernel/sched/core.c:8110 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] do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623 mark_inode_dirty_sync include/linux/fs.h:2218 [inline] dquot_claim_block include/linux/quotaops.h:356 [inline] ext4_da_update_reserve_space+0x2ac/0x730 fs/ext4/inode.c:373 ext4_es_insert_extent+0xa6f/0x10f0 fs/ext4/extents_status.c:1003 ext4_map_create_blocks+0x266/0x5e0 fs/ext4/inode.c:671 ext4_map_blocks+0x46b/0xd30 fs/ext4/inode.c:824 mpage_map_one_extent fs/ext4/inode.c:2396 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2490 [inline] ext4_do_writepages+0x2313/0x3f20 fs/ext4/inode.c:2948 ext4_writepages+0x347/0x790 fs/ext4/inode.c:3042 do_writepages+0x278/0x600 mm/page-writeback.c:2571 __writeback_single_inode+0x164/0x1350 fs/fs-writeback.c:1764 writeback_sb_inodes+0x766/0x1c60 fs/fs-writeback.c:2056 __writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2132 wb_writeback+0x720/0xb90 fs/fs-writeback.c:2243 wb_check_start_all fs/fs-writeback.c:2369 [inline] wb_do_writeback fs/fs-writeback.c:2395 [inline] wb_workfn+0x890/0xc00 fs/fs-writeback.c:2428 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314 process_scheduled_works kernel/workqueue.c:3397 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task jbd2/sda1-8:4955 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:26088 pid:4955 tgid:4955 ppid:2 task_flags:0x240040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 io_schedule+0x8a/0xf0 kernel/sched/core.c:8110 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:123 wait_on_buffer include/linux/buffer_head.h:420 [inline] jbd2_journal_commit_transaction+0x388a/0x6870 fs/jbd2/commit.c:837 kjournald2+0x200/0x760 fs/jbd2/journal.c:201 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz-executor:5614 blocked in I/O wait for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21560 pid:5614 tgid:5614 ppid:5613 task_flags:0x440100 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 io_schedule+0x8a/0xf0 kernel/sched/core.c:8110 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] do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623 generic_update_time fs/inode.c:2198 [inline] file_update_time_flags+0x46b/0x500 fs/inode.c:2428 ext4_page_mkwrite+0x324/0x1890 fs/ext4/inode.c:6753 do_page_mkwrite+0x17a/0x440 mm/memory.c:3668 wp_page_shared mm/memory.c:4069 [inline] do_wp_page+0xa77/0x4350 mm/memory.c:4288 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault+0x1ab6/0x2a00 mm/memory.c:6549 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f5e7b46efc3 RSP: 002b:00007ffc33243150 EFLAGS: 00010202 RAX: 00007f5e785f9db0 RBX: 00007ffc33243280 RCX: 0000000000000000 RDX: 00007f5e785f9dac RSI: 0000000000000008 RDI: 00007ffc33243280 RBP: 00000000000003e6 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffc33243260 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000006250 R14: ffffffffffff9db0 R15: 0000000000000000 INFO: task syz.1.725:9549 blocked in I/O wait for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.725 state:D stack:27128 pid:9549 tgid:9549 ppid:5626 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 io_schedule+0x8a/0xf0 kernel/sched/core.c:8110 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] do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623 generic_update_time fs/inode.c:2198 [inline] file_update_time_flags+0x46b/0x500 fs/inode.c:2428 ext4_page_mkwrite+0x324/0x1890 fs/ext4/inode.c:6753 do_page_mkwrite+0x17a/0x440 mm/memory.c:3668 do_shared_fault mm/memory.c:5969 [inline] do_fault+0x3b5/0x1750 mm/memory.c:6031 do_pte_missing mm/memory.c:4550 [inline] handle_pte_fault mm/memory.c:6411 [inline] __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6549 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f58a4471580 RSP: 002b:00007ffdae17c350 EFLAGS: 00010202 RAX: 0000001b345f6000 RBX: ffffffff821108b9 RCX: 0000001b345f5ff8 RDX: 0000001b34224220 RSI: 0000000000000008 RDI: 00007f58a5345720 RBP: 00000000000001a2 R08: 00007f58a4800000 R09: 00007f58a4802000 R10: 00000000821108bd R11: 0000000000000006 R12: 00007f58a4816038 R13: 000000000000020b R14: ffffffff821104f0 R15: 00007f58a5345720 INFO: task syz.4.724:9555 blocked in I/O wait for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.724 state:D stack:27128 pid:9555 tgid:9555 ppid:8049 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 io_schedule+0x8a/0xf0 kernel/sched/core.c:8110 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] do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623 generic_update_time fs/inode.c:2198 [inline] file_update_time_flags+0x46b/0x500 fs/inode.c:2428 ext4_page_mkwrite+0x324/0x1890 fs/ext4/inode.c:6753 do_page_mkwrite+0x17a/0x440 mm/memory.c:3668 do_shared_fault mm/memory.c:5969 [inline] do_fault+0x3b5/0x1750 mm/memory.c:6031 do_pte_missing mm/memory.c:4550 [inline] handle_pte_fault mm/memory.c:6411 [inline] __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6549 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f77e9a71cf2 RSP: 002b:00007ffe97811610 EFLAGS: 00010202 RAX: 000000000000b008 RBX: 00007f77ea945720 RCX: 0000000000000000 RDX: 0000001b33519000 RSI: 0000000000000008 RDI: 00007f77ea945720 RBP: 0000000000000546 R08: 00007f77e9e00000 R09: 00007f77e9e16128 R10: 0000000000000003 R11: 0000000000000002 R12: ffffffff8b7fab5b R13: 00007f77e9e16128 R14: 0000000000000032 R15: ffffffffffff5000 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e7e5420 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e7e5420 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e7e5420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 6 locks held by kworker/u8:4/57: #0: ffff88801c6ca940 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc900015f7d08 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffff8880373d20d8 (&type->s_umount_key#33){++++}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:565 #3: ffff8880373d0c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x278/0x600 mm/page-writeback.c:2571 #4: ffff8880373f6938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444 #5: ffff8880764930f0 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x45a/0xd30 fs/ext4/inode.c:823 3 locks held by syz-executor/5614: #0: ffff888074c5d308 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310 #1: ffff8880373d2508 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3668 #2: ffff8880373f6938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444 2 locks held by getty/8364: #0: ffff8880379410a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900035492e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211 3 locks held by syz.1.725/9549: #0: ffff88803487a088 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310 #1: ffff8880373d2508 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3668 #2: ffff8880373f6938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444 3 locks held by syz.4.724/9555: #0: ffff88807b498a88 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310 #1: ffff8880373d2508 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3668 #2: ffff8880373f6938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444 ============================================= 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 04/18/2026 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:162 [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+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245