INFO: task syz-executor:4171 blocked for more than 143 seconds. Not tainted 5.15.185-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21344 pid: 4171 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x1b3/0x920 fs/fs-writeback.c:2770 sync_filesystem+0x16d/0x220 fs/sync.c:64 generic_shutdown_super+0x6b/0x300 fs/super.c:448 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1139 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f8bbb68fc57 RSP: 002b:00007ffe59322538 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f8bbb710925 RCX: 00007f8bbb68fc57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe593225f0 RBP: 00007ffe593225f0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe59323680 R13: 00007f8bbb710925 R14: 0000000000063f48 R15: 00007ffe593236c0 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11bfa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:3/1184: 4 locks held by kworker/u4:5/3091: 1 lock held by syslogd/3530: 1 lock held by udevd/3548: #0: ffff8880201b8518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 2 locks held by getty/3948: #0: ffff88802bdfb098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025be2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 6 locks held by syz-executor/4169: 2 locks held by syz-executor/4171: #0: ffff88802b3580e0 (&type->s_umount_key#56){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffff8881475247d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881475247d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x197/0x920 fs/fs-writeback.c:2768 4 locks held by kworker/u4:6/4266: #0: ffff8880187a0938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90003effd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff88802b358650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x1f1/0xd90 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffff8880602778e8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x21e/0xd90 fs/xfs/libxfs/xfs_bmap.c:4578 1 lock held by udevd/4271: #0: ffff8880201b8518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 4 locks held by kworker/0:11/5114: 2 locks held by kworker/1:13/5197: 1 lock held by syz.6.1442/11222: #0: ffff888022cd60e0 (&type->s_umount_key#55/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229 3 locks held by syz.5.1450/11243: #0: ffffffff8c6068e8 (uuid_mutex){+.+.}-{3:3}, at: btrfs_mount_root+0x262/0x8c0 fs/btrfs/super.c:1708 #1: ffff8880201b8518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #2: ffff88814752c468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2071 1 lock held by syz.8.1453/11261: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.185-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5114 Comm: kworker/0:11 Not tainted 5.15.185-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: xfs-buf/loop3 xfs_buf_ioend_work RIP: 0010:unwind_next_frame+0x8e8/0x1d90 arch/x86/kernel/unwind_orc.c:535 Code: 01 43 0f b6 04 2c 84 c0 0f 85 20 0f 00 00 4c 89 fa 48 c1 ea 03 42 0f b6 04 2a 84 c0 0f 85 2c 0f 00 00 41 0f b6 46 01 83 e0 03 24 c5 70 76 08 8a 48 89 54 24 50 48 8d 7b 08 48 89 f8 48 c1 e8 RSP: 0018:ffffc90000007688 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffc90000007748 RCX: ffffffff8dd8151c RDX: 1ffffffff1ce7c0f RSI: ffffffff8e73e06a RDI: ffffc900032cf9e0 RBP: ffffc90000007790 R08: 0000000000000003 R09: 000000000000000e R10: fffff52000000ef5 R11: 1ffff92000000ef3 R12: 1ffffffff1ce7c0f R13: dffffc0000000000 R14: ffffffff8e73e07a R15: ffffffff8e73e07b FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555570e45c8 CR3: 00000000724f5000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122 kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 insert_work+0x54/0x3d0 kernel/workqueue.c:1366 __queue_work+0x9c5/0xd50 kernel/workqueue.c:1532 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1491 [inline] __run_timers+0x550/0x7c0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:console_unlock+0xd90/0x1200 kernel/printk/printk.c:2749 Code: 00 48 83 7c 24 28 00 75 19 e8 ec 9e 18 00 eb 18 e8 e5 9e 18 00 e8 80 49 42 08 48 83 7c 24 28 00 74 e7 e8 d3 9e 18 00 fb 31 ff <89> de e8 29 a2 18 00 85 db 0f 94 c0 22 44 24 17 3c 01 75 1f e8 b7 RSP: 0018:ffffc900032cf620 EFLAGS: 00000246 RAX: ffffffff815f234d RBX: 0000000000000000 RCX: ffff88802bd73b80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900032cf890 R08: dffffc0000000000 R09: fffffbfff1ff3619 R10: fffffbfff1ff3619 R11: 1ffffffff1ff3618 R12: 1ffffffff194c725 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffffffff194c71e vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274 _printk+0xcc/0x110 kernel/printk/printk.c:2299 __xfs_printk fs/xfs/xfs_message.c:24 [inline] xfs_alert_tag+0x1c8/0x2c0 fs/xfs/xfs_message.c:82 xfs_buf_verifier_error+0x14c/0x290 fs/xfs/xfs_error.c:407 xfs_agf_read_verify+0x1cd/0x250 fs/xfs/libxfs/xfs_alloc.c:-1 xfs_buf_ioend+0x25c/0x6e0 fs/xfs/xfs_buf.c:1263 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287