INFO: task syz.3.20:6471 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.20 state:D stack:24664 pid:6471 tgid:6468 ppid:6341 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0x164/0x360 kernel/sched/core.c:7282 xlog_wait fs/xfs/xfs_log_priv.h:604 [inline] xlog_wait_on_iclog+0x487/0x6e0 fs/xfs/xfs_log.c:791 xlog_force_lsn+0x4e5/0x980 fs/xfs/xfs_log.c:2951 xfs_log_force_seq+0x1c9/0x440 fs/xfs/xfs_log.c:2988 __xfs_trans_commit+0x7e2/0xbf0 fs/xfs/xfs_trans.c:877 xfs_trans_commit+0x13e/0x1c0 fs/xfs/xfs_trans.c:926 xfs_sync_sb_buf+0x13f/0x230 fs/xfs/libxfs/xfs_sb.c:1490 xfs_ioc_setlabel+0x1de/0x340 fs/xfs/xfs_ioctl.c:1060 xfs_file_ioctl+0x9c5/0x16d0 fs/xfs/xfs_ioctl.c:1217 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f15f9b5a539 RSP: 002b:00007f15f91be028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f15f9dc5fa0 RCX: 00007f15f9b5a539 RDX: 00002000000001c0 RSI: 0000000041009432 RDI: 0000000000000004 RBP: 00007f15f9bedee0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f15f9dc6038 R14: 00007f15f9dc5fa0 R15: 00007fff2b5dd418 INFO: task syz.3.20:6499 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.20 state:D stack:27128 pid:6499 tgid:6468 ppid:6341 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x1681/0x54c0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0x164/0x360 kernel/sched/core.c:7282 schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75 ___down_common kernel/locking/semaphore.c:289 [inline] __down_common+0x3d0/0x850 kernel/locking/semaphore.c:314 down+0x80/0xd0 kernel/locking/semaphore.c:100 xfs_buf_lock+0x153/0x4c0 fs/xfs/xfs_buf.c:903 xfs_buf_item_unpin+0x1c4/0x710 fs/xfs/xfs_buf_item.c:551 xlog_cil_ail_insert fs/xfs/xfs_log_cil.c:-1 [inline] xlog_cil_committed+0x9e3/0x1150 fs/xfs/xfs_log_cil.c:995 xlog_cil_process_committed+0x15c/0x1b0 fs/xfs/xfs_log_cil.c:1025 xlog_state_shutdown_callbacks+0x277/0x380 fs/xfs/xfs_log.c:438 xlog_force_shutdown+0x332/0x400 fs/xfs/xfs_log.c:3408 xfs_do_force_shutdown+0x2ae/0x6d0 fs/xfs/xfs_fsops.c:507 xfs_fs_goingdown+0x71/0x150 fs/xfs/xfs_fsops.c:-1 xfs_file_ioctl+0x1325/0x16d0 fs/xfs/xfs_ioctl.c:1392 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f15f9b5a539 RSP: 002b:00007f15f919d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f15f9dc6090 RCX: 00007f15f9b5a539 RDX: 0000200000000080 RSI: 000000008004587d RDI: 0000000000000005 RBP: 00007f15f9bedee0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f15f9dc6128 R14: 00007f15f9dc6090 R15: 00007fff2b5dd418 Showing all locks held in the system: 4 locks held by pr/legacy/17: 3 locks held by kworker/1:0/31: 1 lock held by khungtaskd/37: #0: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/1:1/48: #0: ffff88803c588538 ((wq_completion)xfs-sync/loop0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88803c588538 ((wq_completion)xfs-sync/loop0){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90000ba7c40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90000ba7c40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 2 locks held by kworker/u8:5/87: #0: ffff88805d2ab938 ((wq_completion)xfs-cil/loop6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88805d2ab938 ((wq_completion)xfs-cil/loop6){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90002f3fc40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90002f3fc40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 5 locks held by kworker/u8:8/409: 2 locks held by kworker/u8:10/1235: #0: ffff88805a2f2138 ((wq_completion)xfs-cil/loop9){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88805a2f2138 ((wq_completion)xfs-cil/loop9){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc900061bfc40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc900061bfc40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 2 locks held by kworker/u8:12/2877: #0: ffff888057108138 ((wq_completion)xfs-cil/loop0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff888057108138 ((wq_completion)xfs-cil/loop0){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc9000d8ffc40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc9000d8ffc40 ((work_completion)(&ctx->push_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 2 locks held by getty/5570: #0: ffff888037e4e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 2 locks held by kworker/1:4/5929: #0: ffff88801178e938 ((wq_completion)xfs-sync/loop6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801178e938 ((wq_completion)xfs-sync/loop6){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90003e17c40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90003e17c40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 1 lock held by syz.3.20/6471: #0: ffff888060a0c480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 1 lock held by syz.4.31/6810: #0: ffff88803ea88480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 1 lock held by syz.2.33/6850: #0: ffff8880650d6480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 1 lock held by syz.0.39/6982: #0: ffff88802d57a480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 1 lock held by syz.1.45/7141: #0: ffff88803f2c2480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 1 lock held by syz.5.63/7380: #0: ffff88803517a480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 1 lock held by syz.7.69/7470: #0: ffff8880119e0480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 1 lock held by syz.6.77/7575: #0: ffff88803e9a8480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 1 lock held by syz.9.82/7652: #0: ffff88805ce2e480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 1 lock held by syz.8.93/7771: #0: ffff8880353ae480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x210 fs/namespace.c:537 2 locks held by kworker/0:7/7871: #0: ffff888060d43538 ((wq_completion)xfs-sync/loop9){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff888060d43538 ((wq_completion)xfs-sync/loop9){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc900068dfc40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc900068dfc40 ((work_completion)(&(&log->l_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 2 locks held by syz.4.281/8257: 3 locks held by syz.2.282/8259: 3 locks held by syz.0.283/8261: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:get_lock_parent_ip include/linux/ftrace.h:1168 [inline] RIP: 0010:preempt_latency_start kernel/sched/core.c:5836 [inline] RIP: 0010:preempt_count_add+0x91/0x190 kernel/sched/core.c:5861 Code: 09 de 10 0f b6 c0 3d f5 00 00 00 73 5d 65 8b 05 85 09 de 10 25 ff ff ff 7f 39 f8 75 42 48 8b 5c 24 18 48 89 df e8 2f 41 0d 00 <85> c0 74 09 31 db 31 ff e8 22 41 0d 00 65 4c 8b 35 32 09 de 10 49 RSP: 0018:ffffc900001679b0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff8b2a4835 RCX: ffffffff997d1300 RDX: 000000000000009e RSI: ffffffff8ba732c0 RDI: ffffffff8b2a4835 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff8b2a47d0 R12: 1ffffffff33718f6 R13: 00000000ffffffff R14: 0000009eda8f8dca R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888126204000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f50abd77dac CR3: 00000000357b0000 CR4: 00000000003526f0 Call Trace: delay_tsc+0x65/0xc0 arch/x86/lib/delay.c:79 udelay include/asm-generic/delay.h:62 [inline] wait_for_lsr+0x166/0x2f0 drivers/tty/serial/8250/8250_port.c:1976 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3207 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3290 [inline] serial8250_console_write+0x1391/0x1b90 drivers/tty/serial/8250/8250_port.c:3357 console_emit_next_record kernel/printk/printk.c:3163 [inline] console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3269 legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712 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