INFO: task syz-executor:5646 blocked 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:21984 pid:5646 tgid:5646 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
wb_wait_for_completion+0x3b2/0x700 fs/fs-writeback.c:227
sync_inodes_sb+0x224/0xbf0 fs/fs-writeback.c:3030
sync_filesystem+0x17a/0x230 fs/sync.c:64
generic_shutdown_super+0x77/0x2d0 fs/super.c:626
kill_block_super+0x44/0x90 fs/super.c:1665
xfs_kill_sb+0x15/0x50 fs/xfs/xfs_super.c:2286
deactivate_locked_super+0xbc/0x130 fs/super.c:477
cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317
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:70 [inline]
exit_to_user_mode_loop+0x1fa/0x730 kernel/entry/common.c:101
__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+0x353/0x580 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4d9899f097
RSP: 002b:00007ffe7ea7ceb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f4d98a332ca RCX: 00007f4d9899f097
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe7ea7cf70
RBP: 00007ffe7ea7cf70 R08: 00007ffe7ea7df70 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe7ea7e000
R13: 00007f4d98a332ca R14: 000000000003edda R15: 00007ffe7ea7e040
Showing all locks held in the system:
1 lock held by khungtaskd/32:
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
7 locks held by kworker/u8:8/1156:
2 locks held by getty/5374:
#0: ffff888035af90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5646:
#0: ffff8880347480d8 (&type->s_umount_key#61){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880347480d8 (&type->s_umount_key#61){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880347480d8 (&type->s_umount_key#61){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:509
#1: ffff888026938870 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:396 [inline]
#1: ffff888026938870 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x208/0xbf0 fs/fs-writeback.c:3028
1 lock held by syz-executor/10994:
1 lock held by syz.8.1928/11985:
=============================================
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 06/10/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
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+0xfd7/0x1030 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1156 Comm: kworker/u8:8 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
Workqueue: writeback wb_workfn (flush-7:5)
RIP: 0010:debug_smp_processor_id+0x0/0x20 lib/smp_processor_id.c:57
Code: 60 de c2 8e 4c 89 f6 e8 7e 1a 41 f9 e9 67 ff ff ff cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 c7 c7 20 d3 4b 8c 48 c7 c6 60 d3 4b 8c eb 1c 66 66
RSP: 0018:ffffc90005915980 EFLAGS: 00000002
RAX: 0000000000000003 RBX: 0000000000000993 RCX: ffffffff9a77c503
RDX: 00000000000000eb RSI: ffffffff8c4bd360 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffff888140e88237 R09: 1ffff110281d1046
R10: dffffc0000000000 R11: ffffffff8bcd4740 R12: 1ffffffff355a46e
R13: 00000000ffffffff R14: 000000ebfa220363 R15: 00000000000000dc
FS: 0000000000000000(0000) GS:ffff888124f59000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fea51b8c000 CR3: 0000000061ac0000 CR4: 0000000000350ef0
Call Trace:
delay_tsc+0x6a/0xc0 arch/x86/lib/delay.c:90
udelay include/asm-generic/delay.h:62 [inline]
wait_for_lsr+0x147/0x2f0 drivers/tty/serial/8250/8250_port.c:1988
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3229 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3294 [inline]
serial8250_console_write+0x12ef/0x1ba0 drivers/tty/serial/8250/8250_port.c:3379
console_emit_next_record kernel/printk/printk.c:3183 [inline]
console_flush_one_record kernel/printk/printk.c:3269 [inline]
console_flush_all+0x6ea/0xaf0 kernel/printk/printk.c:3343
__console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3413
vprintk_emit+0x485/0x560 kernel/printk/printk.c:2479
_printk+0xdd/0x130 kernel/printk/printk.c:2504
print_hex_dump+0x1d2/0x2b0 lib/hexdump.c:286
xfs_hex_dump+0x3d/0x50 fs/xfs/xfs_message.c:110
xfs_buf_verifier_error+0x1cc/0x2a0 fs/xfs/xfs_error.c:330
xfs_agfl_read_verify+0x17f/0x200 fs/xfs/libxfs/xfs_alloc.c:-1
xfs_buf_ioend+0x31b/0x750 fs/xfs/xfs_buf.c:1119
xfs_buf_iowait+0x133/0x420 fs/xfs/xfs_buf.c:1316
_xfs_buf_read fs/xfs/xfs_buf.c:621 [inline]
xfs_buf_read_map+0x31f/0xa00 fs/xfs/xfs_buf.c:687
xfs_trans_read_buf_map+0x235/0x820 fs/xfs/xfs_trans_buf.c:273
xfs_trans_read_buf fs/xfs/xfs_trans.h:212 [inline]
xfs_alloc_read_agfl+0x22c/0x440 fs/xfs/libxfs/xfs_alloc.c:885
xfs_alloc_fix_freelist+0x1183/0x1c60 fs/xfs/libxfs/xfs_alloc.c:2961
xfs_alloc_vextent_prepare_ag+0xda/0x650 fs/xfs/libxfs/xfs_alloc.c:3566
xfs_alloc_vextent_iterate_ags+0x147/0x960 fs/xfs/libxfs/xfs_alloc.c:3750
xfs_alloc_vextent_start_ag+0x373/0x850 fs/xfs/libxfs/xfs_alloc.c:3839
xfs_bmap_btalloc_best_length fs/xfs/libxfs/xfs_bmap.c:3617 [inline]
xfs_bmap_btalloc fs/xfs/libxfs/xfs_bmap.c:3661 [inline]
xfs_bmapi_allocate+0x18d1/0x2f20 fs/xfs/libxfs/xfs_bmap.c:3936
xfs_bmapi_convert_one_delalloc fs/xfs/libxfs/xfs_bmap.c:4445 [inline]
xfs_bmapi_convert_delalloc+0x879/0x1540 fs/xfs/libxfs/xfs_bmap.c:4501
xfs_map_blocks fs/xfs/xfs_aops.c:461 [inline]
xfs_writeback_range+0x6ab/0xf80 fs/xfs/xfs_aops.c:505
iomap_writeback_range fs/iomap/buffered-io.c:1862 [inline]
iomap_writeback_folio+0x14f1/0x2790 fs/iomap/buffered-io.c:1988
iomap_writepages+0x167/0x2e0 fs/iomap/buffered-io.c:2051
xfs_vm_writepages+0x2eb/0x3d0 fs/xfs/xfs_aops.c:719
do_writepages+0x338/0x560 mm/page-writeback.c:2571
__writeback_single_inode+0x12e/0xf90 fs/fs-writeback.c:1787
writeback_sb_inodes+0x9de/0x1b00 fs/fs-writeback.c:2079
wb_writeback+0x41c/0xad0 fs/fs-writeback.c:2264
wb_do_writeback fs/fs-writeback.c:2432 [inline]
wb_workfn+0x431/0x10f0 fs/fs-writeback.c:2477
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
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