INFO: task kworker/0:8:18219 blocked for more than 143 seconds.
Not tainted 6.6.101-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:8 state:D stack:24616 pid:18219 ppid:2 flags:0x00004000
Workqueue: xfs-sync/loop5 xfs_flush_inodes_worker
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:192
sync_inodes_sb+0x1bc/0x9e0 fs/fs-writeback.c:2761
xfs_flush_inodes_worker+0x61/0x80 fs/xfs/xfs_super.c:617
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
INFO: task syz.5.3256:20420 blocked for more than 144 seconds.
Not tainted 6.6.101-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.3256 state:D stack:23632 pid:20420 ppid:20244 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_timeout+0x9b/0x280 kernel/time/timer.c:2143
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x2bd/0x590 kernel/sched/completion.c:148
__flush_work+0x895/0x9f0 kernel/workqueue.c:3430
xfs_file_buffered_write+0x33c/0x940 fs/xfs/xfs_file.c:801
__kernel_write_iter+0x274/0x670 fs/read_write.c:517
dump_emit_page fs/coredump.c:957 [inline]
dump_user_range+0x3f6/0x800 fs/coredump.c:984
elf_core_dump+0x3114/0x36e0 fs/binfmt_elf.c:2184
do_coredump+0x1755/0x2480 fs/coredump.c:833
get_signal+0x1133/0x1400 kernel/signal.c:2888
arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:315
exc_page_fault+0x8f/0x110 arch/x86/mm/fault.c:1524
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7feaadf8ebf1
RSP: 002b:0000000000000050 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007feaae1b6180 RCX: 00007feaadf8ebe9
RDX: 0000000000000000 RSI: 0000000000000050 RDI: 0000000000904000
RBP: 00007feaae011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007feaae1b6218 R14: 00007feaae1b6180 R15: 00007fffe7c1b888
Showing all locks held in the system:
3 locks held by kworker/u4:1/12:
#0:
ffff888017873938
((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc90000117d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90000117d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2:
ffffffff8cd35a40
(
rcu_state.barrier_mutex
){+.+.}-{3:3}
, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:4089
1 lock held by khungtaskd/29:
#0: ffffffff8cd2fba0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2fba0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2fba0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
4 locks held by kworker/u4:10/4480:
#0: ffff88801a27f938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff88801a27f938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1:
ffffc9000ec37d00
(
(work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:2609 [inline]
, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2:
ffff888065df8608
(
sb_internal
#5
){.+.+}-{0:0}
, at: xfs_bmapi_convert_one_delalloc fs/xfs/libxfs/xfs_bmap.c:4534 [inline]
, at: xfs_bmapi_convert_delalloc+0x2f4/0x1490 fs/xfs/libxfs/xfs_bmap.c:4661
#3: ffff888042c02018 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_bmapi_convert_one_delalloc fs/xfs/libxfs/xfs_bmap.c:4539 [inline]
#3: ffff888042c02018 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x320/0x1490 fs/xfs/libxfs/xfs_bmap.c:4661
2 locks held by getty/5554:
#0: ffff88823bd0c8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
3 locks held by kworker/1:9/5982:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc90004ddfd00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90004ddfd00 (fqdir_free_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8cd35a40 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:4089
4 locks held by kworker/0:8/18219:
#0: ffff88805e53e538 ((wq_completion)xfs-sync/loop5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff88805e53e538 ((wq_completion)xfs-sync/loop5){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1:
ffffc90004cdfd00
(
(work_completion)(&mp->m_flush_inodes_work)
){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:2609 [inline]
, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2:
ffff888065df80e0
(
&type->s_umount_key
#87
){++++}-{3:3}
, at: xfs_flush_inodes_worker+0x45/0x80 fs/xfs/xfs_super.c:616
#3:
ffff8880219d07d0
(
&bdi->wb_switch_rwsem
){+.+.}-{3:3}
, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline]
, at: sync_inodes_sb+0x1a0/0x9e0 fs/fs-writeback.c:2759
2 locks held by syz.5.3256/20420:
#0: ffff888065df8418 (sb_writers#29){.+.+}-{0:0}, at: do_coredump+0x1734/0x2480 fs/coredump.c:832
#1: ffff888042c02248 (&sb->s_type->i_mutex_key#32){++++}-{3:3}, at: xfs_ilock+0xee/0x360 fs/xfs/xfs_inode.c:195
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.6.101-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf41/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15797 Comm: kworker/0:4 Not tainted 6.6.101-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: xfs-buf/loop5 xfs_buf_ioend_work
RIP: 0010:io_serial_in+0x77/0xb0 drivers/tty/serial/8250/8250_port.c:417
Code: e8 9e fa e9 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 7f 40 41 fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 44 89 f9 80 e1 07 38 c1 7c aa 4c
RSP: 0018:ffffc90004f07258 EFLAGS: 00000002
RAX: 1ffffffff2e3a600 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffc90004f07450 R08: ffff888021100237 R09: 1ffff11004220046
R10: dffffc0000000000 R11: ffffed1004220047 R12: dffffc0000000000
R13: 00000000000026f0 R14: ffffffff971d3200 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdfd8383ad8 CR3: 000000003004e000 CR4: 00000000003506f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:117 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:139 [inline]
wait_for_lsr drivers/tty/serial/8250/8250_port.c:2084 [inline]
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3368 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3390 [inline]
serial8250_console_write+0xf2a/0x17a0 drivers/tty/serial/8250/8250_port.c:3475
console_emit_next_record kernel/printk/printk.c:2944 [inline]
console_flush_all+0x6cd/0xd00 kernel/printk/printk.c:3000
console_unlock+0xae/0x340 kernel/printk/printk.c:3069
vprintk_emit+0x477/0x600 kernel/printk/printk.c:2341
_printk+0xd0/0x110 kernel/printk/printk.c:2366
print_hex_dump+0x1a9/0x260 lib/hexdump.c:285
xfs_hex_dump+0x3d/0x50 fs/xfs/xfs_message.c:110
xfs_buf_verifier_error+0x1cc/0x2a0 fs/xfs/xfs_error.c:460
xfs_agf_read_verify+0x1d5/0x250 fs/xfs/libxfs/xfs_alloc.c:-1
xfs_buf_ioend+0x260/0x6f0 fs/xfs/xfs_buf.c:1309
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293