INFO: task syz-executor:5622 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:syz-executor state:D stack:22400 pid:5622 tgid:5622 ppid:5621 task_flags:0x440100 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5583 [inline] __schedule+0x17dd/0x5830 kernel/sched/core.c:7382 __schedule_loop kernel/sched/core.c:7459 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7474 io_schedule+0x7f/0xd0 kernel/sched/core.c:8146 bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258 __wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:106 [inline] do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7451 __ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7642 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7679 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x399/0x440 fs/inode.c:2483 ext4_page_mkwrite+0x21f/0x1470 fs/ext4/inode.c:7864 do_page_mkwrite+0x147/0x310 mm/memory.c:3881 wp_page_shared mm/memory.c:4285 [inline] do_wp_page+0x1a85/0x4b80 mm/memory.c:4508 handle_pte_fault mm/memory.c:6681 [inline] __handle_mm_fault mm/memory.c:6806 [inline] handle_mm_fault+0x19c9/0x2f80 mm/memory.c:6973 do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7f13d1a7dad6 RSP: 002b:00007ffc01002480 EFLAGS: 00010202 RAX: 00007f13cfb3c000 RBX: 000055555f766b40 RCX: 0000000000000005 RDX: 0000000000000f3d RSI: 000055555f76ae40 RDI: 0000000000000020 RBP: 00007ffc01002980 R08: 000055555f76af38 R09: 00000000000000a1 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffc010027c0 R13: 00007ffc010025b0 R14: 585858582e7a7973 R15: 00007ffc01002500 INFO: task syz.1.1776:10816 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:syz.1.1776 state:D stack:24584 pid:10816 tgid:10816 ppid:5649 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5583 [inline] __schedule+0x17dd/0x5830 kernel/sched/core.c:7382 __schedule_loop kernel/sched/core.c:7459 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7474 io_schedule+0x7f/0xd0 kernel/sched/core.c:8146 bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258 __wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:106 [inline] do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7451 __ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7642 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7679 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x399/0x440 fs/inode.c:2483 ext4_page_mkwrite+0x21f/0x1470 fs/ext4/inode.c:7864 do_page_mkwrite+0x147/0x310 mm/memory.c:3881 do_shared_fault mm/memory.c:6177 [inline] do_fault mm/memory.c:6239 [inline] do_pte_missing+0x70f/0x3570 mm/memory.c:4768 handle_pte_fault mm/memory.c:6654 [inline] __handle_mm_fault mm/memory.c:6806 [inline] handle_mm_fault+0x1807/0x2f80 mm/memory.c:6973 do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7f4061a73ba9 RSP: 002b:00007ffdd0a8df30 EFLAGS: 00010202 RAX: 0000001b34d23000 RBX: ffffffff8bfca18f RCX: 0000001b34d22ff8 RDX: 0000001b3492421c RSI: 0000000000000008 RDI: 00007f4062955720 RBP: 00000000000001fb R08: 00007f4061e10000 R09: 00007f4061e12000 R10: 000000008bfca193 R11: 0000000000000002 R12: 00007f4061e26038 R13: 00000000000005b8 R14: ffffffff8bfca6ce R15: 00007f4062955720 Showing all locks held in the system: locks held by kworker/u8:1/14: 6, on CPU#0: #0: ffff888021a9b948 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff888021a9b948 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff888021a9b948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] #0: ffff888021a9b948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #1: ffffc90000137c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90000137c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90000137c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline] #1: ffffc90000137c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578 #2: ffff8880374ba0e8 (&type->s_umount_key#34){++++}-{4:4}, at: super_trylock_shared+0x23/0xf0 fs/super.c:670 #3: ffff888036898cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1f1/0x4e0 fs/ext4/inode.c:3170 #4: ffff8880374b8950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444 #5: ffff888076994a98 (&ei->i_data_sem#2){++++}-{4:4}, at: ext4_map_blocks+0xacb/0x1c60 fs/ext4/inode.c:926 locks held by khungtaskd/35: 1, last CPU#0: #0: ffffffff9015a4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff9015a4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff9015a4a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by getty/5391: 2, on CPU#0: #0: ffff88803733b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032362e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 locks held by syz-executor/5622: 3, on CPU#0: #0: ffff88802a21c088 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:337 #1: ffff8880374ba558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff8880374ba558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fe/0x1470 fs/ext4/inode.c:7863 #2: ffff8880374b8950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444 locks held by syz.6.1770/10800: 3, on CPU#0: #0: ffff88807f01b1c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:337 #1: ffff8880374ba558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff8880374ba558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fe/0x1470 fs/ext4/inode.c:7863 #2: ffff8880374b8950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444 locks held by syz.0.1775/10813: 3, on CPU#0: #0: ffff88801cfb0a88 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:337 #1: ffff8880374ba558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff8880374ba558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fe/0x1470 fs/ext4/inode.c:7863 #2: ffff8880374b8950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444 locks held by syz.1.1776/10816: 3, on CPU#0: #0: ffff888075eadbc8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:337 #1: ffff8880374ba558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff8880374ba558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fe/0x1470 fs/ext4/inode.c:7863 #2: ffff8880374b8950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 35 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123 nmi_trigger_cpumask_backtrace+0x17d/0x390 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+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:377 [inline] watchdog+0x1073/0x10f0 kernel/hung_task.c:598 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245