INFO: task kworker/u4:7:2643 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:7 state:D stack:12568 pid:2643 ppid:2 flags:0x00004000 Workqueue: xfs-cil/loop3 xlog_cil_push_work Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x56d/0x870 kernel/sched/core.c:6561 schedule+0x50/0xb0 kernel/sched/core.c:6637 schedule_timeout+0x29/0x180 kernel/time/timer.c:1941 ___down_common kernel/locking/semaphore.c:229 [inline] __down_common+0xf1/0x220 kernel/locking/semaphore.c:250 down+0x38/0x40 kernel/locking/semaphore.c:64 xfs_buf_lock+0x4d/0x110 fs/xfs/xfs_buf.c:1120 xfs_buf_item_unpin+0x81/0x1c0 fs/xfs/xfs_buf_item.c:582 xfs_trans_committed_bulk+0x12b/0x2e0 fs/xfs/xfs_trans.c:808 xlog_cil_committed+0xa3/0x340 fs/xfs/xfs_log_cil.c:795 xlog_cil_push_work+0x991/0xa80 fs/xfs/xfs_log_cil.c:1405 process_one_work+0x27d/0x4c0 kernel/workqueue.c:2292 worker_thread+0x236/0x3a0 kernel/workqueue.c:2439 kthread+0xcc/0xe0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task syz.3.48:4479 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.48 state:D stack:14640 pid:4479 ppid:2935 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x56d/0x870 kernel/sched/core.c:6561 schedule+0x50/0xb0 kernel/sched/core.c:6637 schedule_timeout+0x29/0x180 kernel/time/timer.c:1941 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common+0xf8/0x1b0 kernel/sched/completion.c:117 __flush_workqueue+0x2fd/0x590 kernel/workqueue.c:2864 xlog_cil_push_now fs/xfs/xfs_log_cil.c:1521 [inline] xlog_cil_force_seq+0x94/0x2a0 fs/xfs/xfs_log_cil.c:1723 xfs_log_force_seq+0x87/0x170 fs/xfs/xfs_log.c:3370 __xfs_trans_commit+0x2c7/0x360 fs/xfs/xfs_trans.c:1013 xfs_sync_sb_buf+0x64/0xa0 fs/xfs/libxfs/xfs_sb.c:1162 xfs_ioc_setlabel fs/xfs/xfs_ioctl.c:1827 [inline] xfs_file_ioctl+0x47a/0xc90 fs/xfs/xfs_ioctl.c:1925 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x65/0xb0 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fad7318ebe9 RSP: 002b:00007fad72fde038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fad733b6090 RCX: 00007fad7318ebe9 RDX: 0000200000000100 RSI: 0000000041009432 RDI: 0000000000000004 RBP: 00007fad73211e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fad733b6128 R14: 00007fad733b6090 R15: 00007ffd84c2e308 Showing all locks held in the system: 2 locks held by kworker/u4:0/9: #0: ffff8881297f7d38 ((wq_completion)xfs-cil/loop5){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 #1: ffffc90000053e68 ((work_completion)(&ctx->push_work)){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 1 lock held by rcu_tasks_kthre/12: #0: ffffffff831859e8 (rcu_tasks.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_one_gp kernel/rcu/tasks.h:517 [inline] #0: ffffffff831859e8 (rcu_tasks.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_kthread+0x97/0x4c0 kernel/rcu/tasks.h:562 1 lock held by rcu_tasks_trace/13: #0: ffffffff83186010 (rcu_tasks_trace.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_one_gp kernel/rcu/tasks.h:517 [inline] #0: ffffffff83186010 (rcu_tasks_trace.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_kthread+0x97/0x4c0 kernel/rcu/tasks.h:562 2 locks held by kworker/0:1/17: #0: ffff888100062538 ((wq_completion)events){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 #1: ffffc90000093e68 ((work_completion)(&pwq->unbound_release_work)){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 3 locks held by kworker/1:1/27: #0: ffff888100062538 ((wq_completion)events){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 #1: ffffc900000efe68 ((work_completion)(&pwq->unbound_release_work)){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 #2: ffffffff83186a78 (rcu_state.exp_mutex){....}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff83186a78 (rcu_state.exp_mutex){....}-{3:3}, at: synchronize_rcu_expedited+0x220/0x750 kernel/rcu/tree_exp.h:962 1 lock held by khungtaskd/28: #0: ffffffff831857a8 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff831857a8 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff831857a8 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x2a/0xf0 kernel/locking/lockdep.c:6513 2 locks held by kworker/0:2/999: #0: ffff888129753f38 ((wq_completion)xfs-sync/loop5){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 #1: ffffc90001a1be68 ((work_completion)(&(&log->l_work)->work)){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 2 locks held by kworker/0:3/1599: #0: ffff888124b84938 ((wq_completion)xfs-sync/loop3){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 #1: ffffc900080a3e68 ((work_completion)(&(&log->l_work)->work)){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 2 locks held by getty/1953: #0: ffff8881001a6898 (&tty->ldisc_sem){....}-{0:0}, at: tty_ldisc_ref_wait+0x1c/0x40 drivers/tty/tty_ldisc.c:244 #1: ffffc900080af2f0 (&ldata->atomic_read_lock){....}-{3:3}, at: n_tty_read+0x19e/0x6d0 drivers/tty/n_tty.c:2198 2 locks held by kworker/u4:7/2643: #0: ffff888124c68938 ((wq_completion)xfs-cil/loop3){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 #1: ffffc90000ecbe68 ((work_completion)(&ctx->push_work)){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 1 lock held by syz-executor/2927: #0: ffff88812c0bb0e0 (&type->s_umount_key#46){....}-{3:3}, at: deactivate_super+0x2a/0x40 fs/super.c:362 1 lock held by syz.3.48/4479: #0: ffff888123a6e438 (sb_writers#13){....}-{0:0}, at: xfs_ioc_setlabel fs/xfs/xfs_ioctl.c:1809 [inline] #0: ffff888123a6e438 (sb_writers#13){....}-{0:0}, at: xfs_file_ioctl+0x432/0xc90 fs/xfs/xfs_ioctl.c:1925 2 locks held by kworker/1:4/4737: #0: ffff888100063138 ((wq_completion)rcu_gp){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 #1: ffffc900080f7e68 ((work_completion)(&rew->rew_work)){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 1 lock held by syz.5.227/6567: #0: ffff888123a6b438 (sb_writers#13){....}-{0:0}, at: xfs_ioc_setlabel fs/xfs/xfs_ioctl.c:1809 [inline] #0: ffff888123a6b438 (sb_writers#13){....}-{0:0}, at: xfs_file_ioctl+0x432/0xc90 fs/xfs/xfs_ioctl.c:1925 1 lock held by syz.4.356/8019: #0: ffff888123a6f438 (sb_writers#13){....}-{0:0}, at: xfs_ioc_setlabel fs/xfs/xfs_ioctl.c:1809 [inline] #0: ffff888123a6f438 (sb_writers#13){....}-{0:0}, at: xfs_file_ioctl+0x432/0xc90 fs/xfs/xfs_ioctl.c:1925 1 lock held by syz-executor/9212: #0: ffff88812c2e60e0 (&type->s_umount_key#46){....}-{3:3}, at: deactivate_super+0x2a/0x40 fs/super.c:362 2 locks held by kworker/0:7/10408: #0: ffff888100062538 ((wq_completion)events){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 #1: ffffc9000a753e68 ((work_completion)(&pwq->unbound_release_work)){....}-{0:0}, at: process_one_work+0x223/0x4c0 kernel/workqueue.c:2267 1 lock held by syz.7.770/12755: #0: ffff88812c0be438 (sb_writers#13){....}-{0:0}, at: xfs_ioc_setlabel fs/xfs/xfs_ioctl.c:1809 [inline] #0: ffff88812c0be438 (sb_writers#13){....}-{0:0}, at: xfs_file_ioctl+0x432/0xc90 fs/xfs/xfs_ioctl.c:1925 1 lock held by syz-executor/13873: #0: ffff88812e1a80e0 (&type->s_umount_key#46){....}-{3:3}, at: deactivate_super+0x2a/0x40 fs/super.c:362 1 lock held by syz.1.912/14483: #0: ffff88811cb06438 (sb_writers#13){....}-{0:0}, at: xfs_ioc_setlabel fs/xfs/xfs_ioctl.c:1809 [inline] #0: ffff88811cb06438 (sb_writers#13){....}-{0:0}, at: xfs_file_ioctl+0x432/0xc90 fs/xfs/xfs_ioctl.c:1925 1 lock held by syz-executor/15581: #0: ffff88812d7160e0 (&type->s_umount_key#46){....}-{3:3}, at: deactivate_super+0x2a/0x40 fs/super.c:362 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x74/0xbb lib/dump_stack.c:106 nmi_cpu_backtrace+0x102/0x160 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0xa5/0x160 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0x533/0x560 kernel/hung_task.c:377 kthread+0xcc/0xe0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:741