INFO: task syz-executor:5576 blocked in I/O wait for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21480 pid:5576 tgid:5576 ppid:5575 task_flags:0x440100 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x1709/0x5530 kernel/sched/core.c:7231 __schedule_loop kernel/sched/core.c:7308 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7323 io_schedule+0x7f/0xd0 kernel/sched/core.c:8151 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250 __wait_on_bit+0xac/0x2f0 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:105 [inline] do_get_write_access+0x670/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d6/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0x1c3/0x590 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6427 __ext4_mark_inode_dirty+0x13e/0x700 fs/ext4/inode.c:6602 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6639 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2709 generic_update_time fs/inode.c:2254 [inline] file_update_time_flags+0x3f4/0x4b0 fs/inode.c:2484 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6805 do_page_mkwrite+0x14a/0x310 mm/memory.c:3761 do_shared_fault mm/memory.c:6021 [inline] do_fault mm/memory.c:6083 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4645 handle_pte_fault mm/memory.c:6503 [inline] __handle_mm_fault mm/memory.c:6652 [inline] handle_mm_fault+0xf95/0x28d0 mm/memory.c:6821 do_user_addr_fault+0xa4d/0x1340 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: 0033:0x7f1971560123 RSP: 002b:00007fff2e93f940 EFLAGS: 00010202 RAX: 00007f196b2e2878 RBX: 00007fff2e93fa70 RCX: 0000000000000000 RDX: 00007f196b2e2874 RSI: 0000000000000008 RDI: 00007fff2e93fa70 RBP: 00000000000003e6 R08: 0000000000000000 R09: 0000000000000000 R10: 00007fff2e93fa50 R11: 0000000000000000 R12: 0000000000000000 R13: 000000000000d788 R14: ffffffffffff2878 R15: 0000000000000000 INFO: task syz.2.6:5760 blocked in I/O wait for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.6 state:D stack:26184 pid:5760 tgid:5760 ppid:5589 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x1709/0x5530 kernel/sched/core.c:7231 __schedule_loop kernel/sched/core.c:7308 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7323 io_schedule+0x7f/0xd0 kernel/sched/core.c:8151 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250 __wait_on_bit+0xac/0x2f0 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:105 [inline] do_get_write_access+0x670/0x1090 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d6/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0x1c3/0x590 fs/ext4/ext4_jbd2.c:241 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6427 __ext4_mark_inode_dirty+0x13e/0x700 fs/ext4/inode.c:6602 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6639 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2709 generic_update_time fs/inode.c:2254 [inline] file_update_time_flags+0x3f4/0x4b0 fs/inode.c:2484 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6805 do_page_mkwrite+0x14a/0x310 mm/memory.c:3761 do_shared_fault mm/memory.c:6021 [inline] do_fault mm/memory.c:6083 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4645 handle_pte_fault mm/memory.c:6503 [inline] __handle_mm_fault mm/memory.c:6652 [inline] handle_mm_fault+0xf95/0x28d0 mm/memory.c:6821 do_user_addr_fault+0xa4d/0x1340 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: 0033:0x7f7af052b9e3 RSP: 002b:00007ffc89b170f0 EFLAGS: 00010246 RAX: 00000000005ffde8 RBX: 0000000000000000 RCX: 0000001b31d64000 RDX: 0000001b31d24000 RSI: 0000000000600000 RDI: 00007f7af08a0708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffc89b17380 Showing all locks held in the system: locks held by khungtaskd/40: 1, last CPU#1: #0: ffffffff8e3c3880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e3c3880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8e3c3880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6835 locks held by kworker/u8:10/1312: 6, on CPU#0: #0: ffff8880206cf138 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffff8880206cf138 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffff8880206cf138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344 #1: ffffc90006dd7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #1: ffffc90006dd7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #1: ffffc90006dd7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344 #2: ffff8880364ba0e0 (&type->s_umount_key#32){++++}-{4:4}, at: super_trylock_shared+0x23/0xf0 fs/super.c:688 #3: ffff888036498cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline] #3: ffff888036498cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1876 [inline] #3: ffff888036498cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3042 #4: ffff8880364aebb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fc3/0x2210 fs/jbd2/transaction.c:444 #5: ffff8880232b9a38 (&ei->i_data_sem#2){++++}-{4:4}, at: ext4_map_blocks+0x7cc/0x1240 fs/ext4/inode.c:823 locks held by getty/5341: 2, on CPU#1: #0: ffff8880369dd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900044cb2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 locks held by syz-executor/5576: 3, on CPU#0: #0: ffff8880217d5e48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6804 #2: ffff8880364aebb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fc3/0x2210 fs/jbd2/transaction.c:444 locks held by syz.1.2/5744: 3, on CPU#1: #0: ffff888037955588 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6804 #2: ffff8880364aebb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fc3/0x2210 fs/jbd2/transaction.c:444 locks held by syz.2.6/5760: 3, on CPU#0: #0: ffff888039ed0bc8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff8880364ba688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6804 #2: ffff8880364aebb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fc3/0x2210 fs/jbd2/transaction.c:444 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 40 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65 trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 0c 74 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 66 19 00 fb f4 4c d0 03 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffffff8e007ca0 EFLAGS: 00000242 RAX: 00000000000cdf7f RBX: ffffffff8199b400 RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8d98ba58 RDI: ffffffff8bcbd080 RBP: ffffffff8e007d78 R08: ffff8880b8633d1b R09: 1ffff110170c67a3 R10: dffffc0000000000 R11: ffffed10170c67a4 R12: 0000000000000000 R13: 1ffffffff1c1edf0 R14: 1ffffffff1c00f9c R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881259f2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000563cf08304f8 CR3: 000000000e1b0000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:767 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:768 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x2e0/0x540 kernel/sched/idle.c:355 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454 rest_init+0x378/0x3a0 init/main.c:727 start_kernel+0x392/0x3e0 init/main.c:1185 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x137/0x1b0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x157