INFO: tas INFO: task jbd2/sda1-8:4940 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:24680 pid:4940 tgid:4940 ppid:2 task_flags:0x240040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7376 io_schedule+0x7f/0xd0 kernel/sched/core.c:8220 bit_wait_io+0x11/0xd0 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_buffer include/linux/buffer_head.h:418 [inline] jbd2_journal_commit_transaction+0x2f1d/0x5b70 fs/jbd2/commit.c:834 kjournald2+0x3bc/0x750 fs/jbd2/journal.c:200 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 INFO: task syz-executor:5599 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:22440 pid:5599 tgid:5599 ppid:5598 task_flags:0x440100 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7376 io_schedule+0x7f/0xd0 kernel/sched/core.c:8220 bit_wait_io+0x11/0xd0 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+0x662/0x1070 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2744 generic_update_time fs/inode.c:2252 [inline] file_update_time_flags+0x399/0x440 fs/inode.c:2482 ext4_page_mkwrite+0x224/0x1140 fs/ext4/inode.c:6902 do_page_mkwrite+0x147/0x310 mm/memory.c:3816 wp_page_shared mm/memory.c:4217 [inline] do_wp_page+0x1a9c/0x4b80 mm/memory.c:4440 handle_pte_fault mm/memory.c:6582 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0x15d7/0x3750 mm/memory.c:6876 do_user_addr_fault+0xa4f/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: 0033:0x7f6fb967c6e2 RSP: 002b:00007fff08159660 EFLAGS: 00010212 RAX: 00007f6fb7834000 RBX: 00005555948809f0 RCX: 0000000000000005 RDX: 0000000000000700 RSI: 000055559487e158 RDI: 0000000000000020 RBP: 00007fff08159b60 R08: 000055559487e178 R09: 00000000000000a3 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff081599a0 R13: 00007fff08159790 R14: 585858582e7a7973 R15: 00007fff081596e0 INFO: task syz.4.1881:11379 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.4.1881 state:D stack:25608 pid:11379 tgid:11379 ppid:5611 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7376 io_schedule+0x7f/0xd0 kernel/sched/core.c:8220 bit_wait_io+0x11/0xd0 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+0x662/0x1070 fs/jbd2/transaction.c:1113 jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263 __ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249 ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2744 generic_update_time fs/inode.c:2252 [inline] file_update_time_flags+0x399/0x440 fs/inode.c:2482 ext4_page_mkwrite+0x224/0x1140 fs/ext4/inode.c:6902 do_page_mkwrite+0x147/0x310 mm/memory.c:3816 do_shared_fault mm/memory.c:6076 [inline] do_fault mm/memory.c:6138 [inline] do_pte_missing+0x757/0x34b0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0x1a53/0x3750 mm/memory.c:6876 do_user_addr_fault+0xa4f/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: 0033:0x7f75e34727a9 RSP: 002b:00007ffeae75c710 EFLAGS: 00010202 RAX: 0000001b33a22000 RBX: ffffffff8a8bdf08 RCX: 0000001b33a21ff8 RDX: 0000001b3342421c RSI: 0000000000000008 RDI: 00007f75e4355720 RBP: 0000000000000102 R08: 00007f75e3810000 R09: 00007f75e3812000 R10: 000000008a8bdf0c R11: 0000000000000002 R12: 00007f75e3826038 R13: 0000000000000479 R14: ffffffff8a8bd2b0 R15: 00007f75e4355720 Showing all locks held in the system: locks held by khungtaskd/32: 1, last CPU#1: #0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by kworker/u8:7/153: 2, last CPU#0: #0: ffff8880325be140 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff8880325be140 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff8880325be140 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff8880325be140 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc90002ec7c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90002ec7c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90002ec7c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc90002ec7c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 locks held by kworker/0:2/1552: 2, last CPU#0: #0: ffff88801b069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801b069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801b069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff88801b069d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc90005b2fc40 ((gc_work).work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc90005b2fc40 ((gc_work).work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc90005b2fc40 ((gc_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc90005b2fc40 ((gc_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 locks held by getty/5369: 2, on CPU#1: #0: ffff88803589b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 locks held by syz-executor/5599: 3, on CPU#1: #0: ffff88807495de48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888034634558 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888034634558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888034634558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888034634558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x202/0x1140 fs/ext4/inode.c:6901 #2: ffff888034630938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by kworker/u8:16/6115: 5, last CPU#0: #0: ffff888053e91940 ((wq_completion)krds_cp_wq#2/0){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff888053e91940 ((wq_completion)krds_cp_wq#2/0){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff888053e91940 ((wq_completion)krds_cp_wq#2/0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff888053e91940 ((wq_completion)krds_cp_wq#2/0){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc900052dfc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc900052dfc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc900052dfc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc900052dfc40 ((work_completion)(&(&cp->cp_conn_w)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffff88807f3ee780 (&tc->t_conn_path_lock){+.+.}-{4:4}, at: rds_tcp_conn_path_connect+0x1cc/0x920 net/rds/tcp_connect.c:118 #3: ffff88802c43b860 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] #3: ffff88802c43b860 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: __inet6_bind+0x301/0xf30 net/ipv6/af_inet6.c:292 #4: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #4: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #4: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: __inet6_bind+0x49b/0xf30 net/ipv6/af_inet6.c:336 locks held by syz.4.1881/11379: 3, on CPU#1: #0: ffff888074aa3e48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888034634558 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888034634558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888034634558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888034634558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x202/0x1140 fs/ext4/inode.c:6901 #2: ffff888034630938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 ============================================= NMI backtrace for cpu 1 CPU: 1 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 08/05/2026 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:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 16 Comm: pr/ttyS0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409 Code: e8 1e 82 54 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 bf 86 c4 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 c5 d7 9c fb cc 44 89 f9 80 e1 07 RSP: 0018:ffffc90000157978 EFLAGS: 00000006 RAX: 1ffffffff35a8605 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020 RBP: ffffc90000157ad0 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: ffffffff857368c0 R12: dffffc0000000000 R13: 1ffffffff35a8662 R14: ffffffff9ad43300 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124cc8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b2630fb168 CR3: 000000000eb48000 CR4: 0000000000350ef0 Call Trace: serial_port_in include/linux/serial_core.h:812 [inline] serial8250_console_write+0xed/0x1200 drivers/tty/serial/8250/8250_port.c:3456 nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1 nbcon_emit_one kernel/printk/nbcon.c:1157 [inline] nbcon_kthread_func+0x679/0x880 kernel/printk/nbcon.c:1271 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