INFO: task kworker/u8:11:1196 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:kworker/u8:11 state:D stack:21856 pid:1196 tgid:1196 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:7) Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x16ec/0x5620 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 io_schedule+0x7f/0xd0 kernel/sched/core.c:8110 TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline] txBegin+0x27d/0xc00 fs/jfs/jfs_txnmgr.c:376 jfs_commit_inode+0x1b3/0x530 fs/jfs/inode.c:107 jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138 write_inode fs/fs-writeback.c:1584 [inline] __writeback_single_inode+0x75d/0x10e0 fs/fs-writeback.c:1827 writeback_sb_inodes+0x97f/0x1980 fs/fs-writeback.c:2056 wb_writeback+0x445/0xb00 fs/fs-writeback.c:2241 wb_do_writeback fs/fs-writeback.c:2388 [inline] wb_workfn+0x3fd/0xf20 fs/fs-writeback.c:2428 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 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 INFO: task syz-executor:7711 blocked 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:22504 pid:7711 tgid:7711 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x16ec/0x5620 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 wb_wait_for_completion+0x3e8/0x790 fs/fs-writeback.c:227 __writeback_inodes_sb_nr+0x24c/0x2d0 fs/fs-writeback.c:2847 sync_filesystem+0xa2/0x250 fs/sync.c:54 generic_shutdown_super+0x77/0x2d0 fs/super.c:625 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xf3/0x4d0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f17e8dde097 RSP: 002b:00007fff7b8dd478 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f17e8e721ca RCX: 00007f17e8dde097 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff7b8dd530 RBP: 00007fff7b8dd530 R08: 00007fff7b8de530 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff7b8de5c0 R13: 00007f17e8e721ca R14: 000000000006835a R15: 00007fff7b8de600 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8dfc8080 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc8080 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8dfc8080 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 7 locks held by kworker/1:2/819: 2 locks held by kworker/u8:11/1196: #0: ffff88801ee86938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff88801ee86938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397 #1: ffffc90006727c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline] #1: ffffc90006727c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397 2 locks held by getty/5347: #0: ffff8880296cc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5600: #0: ffff8880448d20d0 (&type->s_umount_key#130){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880448d20d0 (&type->s_umount_key#130){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880448d20d0 (&type->s_umount_key#130){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e456d38 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441 1 lock held by syz-executor/5601: #0: ffff888062ffe480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 1 lock held by udevd/5707: #0: ffff888037e12480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 1 lock held by udevd/5815: #0: ffff888037e12480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 1 lock held by udevd/5830: 2 locks held by udevd/6112: 1 lock held by udevd/6425: 1 lock held by udevd/6433: #0: ffff88801ca94480 (sb_writers){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 1 lock held by syz-executor/7711: #0: ffff88802ac880d0 (&type->s_umount_key#130){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88802ac880d0 (&type->s_umount_key#130){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88802ac880d0 (&type->s_umount_key#130){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 1 lock held by syz-executor/7826: 1 lock held by syz-executor/9835: 2 locks held by syz-executor/10961: #0: ffff888037fe00d0 (&type->s_umount_key#130){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888037fe00d0 (&type->s_umount_key#130){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888037fe00d0 (&type->s_umount_key#130){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e456d38 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd3/0x1030 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 819 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: wg-crypt-wg0 wg_packet_tx_worker RIP: 0010:__bfs kernel/locking/lockdep.c:-1 [inline] RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline] RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline] RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline] RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline] RIP: 0010:__lock_acquire+0x1968/0x2cf0 kernel/locking/lockdep.c:5237 Code: 89 c1 81 e1 ff 0f 00 00 89 0d 08 56 d3 13 2b 05 fe 55 d3 13 25 ff 0f 00 00 39 05 bf 55 d2 11 73 06 89 05 b7 55 d2 11 48 8b 02 <48> 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 48 8b 00 4c 39 e8 RSP: 0018:ffffc9000592ebb8 EFLAGS: 00000006 RAX: ffffffff9316cb90 RBX: 00000000000003cd RCX: 0000000000000384 RDX: ffffffff95fb79d8 RSI: ffff888020b70ce8 RDI: 00000000000003cd RBP: c7cf077c2542c388 R08: ffffc9000592eb80 R09: 0000000000000020 R10: dffffc0000000000 R11: ffffffff81a0b320 R12: ffffffff961b68f8 R13: ffffffff9316cb90 R14: ffff888020b70000 R15: 0000000000000383 FS: 0000000000000000(0000) GS:ffff888126271000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffdfcbf2fd0 CR3: 00000000349d6000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 do_write_seqcount_begin_nested include/linux/seqlock.h:478 [inline] do_write_seqcount_begin include/linux/seqlock.h:504 [inline] psi_write_begin+0xab/0x160 kernel/sched/psi.c:183 psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 psi_sched_switch kernel/sched/stats.h:225 [inline] __schedule+0x292e/0x5620 kernel/sched/core.c:7183 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x760 kernel/entry/common.c:164 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:0xffffffffa001cf20 Code: e3 cc 41 ff e3 cc 41 ff e3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <41> ff e3 cc 41 ff e3 cc 41 ff e3 cc 41 ff e3 cc 41 ff e3 cc 41 ff RSP: 0018:ffffc9000592f180 EFLAGS: 00000246 RAX: ffffffff899b6ae2 RBX: 0000000000010000 RCX: ffff888020b70000 RDX: 0000000000000100 RSI: ffff88802afa3640 RDI: ffff88801b75eb80 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000100 R10: 0000000000000100 R11: ffffffff85f042f0 R12: ffff8880327c0000 R13: ffff88802afa36c1 R14: ffff88801b75eb80 R15: ffff88802afa36c0