INFO: task syz-executor:4192 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:20864 pid: 4192 ppid: 1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191
sync_inodes_sb+0x1b3/0x920 fs/fs-writeback.c:2781
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:1148
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+0xee/0x180 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: 0033:0x7fa33cbefa77
RSP: 002b:00007ffd68e17138 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fa33cc72d7d RCX: 00007fa33cbefa77
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd68e171f0
RBP: 00007ffd68e171f0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd68e18280
R13: 00007fa33cc72d7d R14: 0000000000028236 R15: 00007ffd68e182c0
INFO: task syz.2.400:6297 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.400 state:D stack:26528 pid: 6297 ppid: 4193 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
rwsem_down_read_slowpath+0x528/0x990 kernel/locking/rwsem.c:1055
__down_read_common kernel/locking/rwsem.c:1239 [inline]
__down_read kernel/locking/rwsem.c:1252 [inline]
down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500
iterate_supers+0xa4/0x1d0 fs/super.c:716
ksys_sync+0x91/0x150 fs/sync.c:102
__ia32_sys_sync+0xa/0x10 fs/sync.c:113
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6b52fe5749
RSP: 002b:00007f6b5124c038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f6b5323bfa0 RCX: 00007f6b52fe5749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6b5323bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6b5323c038 R14: 00007f6b5323bfa0 R15: 00007ffdd268ee28
Showing all locks held in the system:
2 locks held by kworker/1:0/21:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:1/144:
#0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc900016cfd00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
2 locks held by kworker/u4:3/155:
#0: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa5/0x140 kernel/sched/core.c:483
#1:
ffff8880b9027888
(
&per_cpu_ptr(group->pcpu, cpu)->seq
){-.-.}-{0:0}
, at: psi_task_switch+0x4d6/0x810 kernel/sched/psi.c:891
2 locks held by getty/3946:
#0:
ffff88802be6e098
(
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1:
ffffc900026562e8
(&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
2 locks held by syz-executor/4183:
#0: ffff8880202bbd18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
#1: ffff888147299468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366
2 locks held by syz-executor/4192:
#0: ffff88802c79e0e0 (&type->s_umount_key#53){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
#1: ffff8881472907d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
#1: ffff8881472907d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x197/0x920 fs/fs-writeback.c:2779
5 locks held by kworker/1:8/4285:
4 locks held by kworker/u4:6/4299:
#0: ffff8880185e8938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000348fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa5/0x140 kernel/sched/core.c:483
#3: ffff888060a93ce8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x21e/0xd90 fs/xfs/libxfs/xfs_bmap.c:4578
1 lock held by syz.2.400/6297:
#0:
ffff88802c79e0e0
(
&type->s_umount_key
#53
){++++}-{3:3}
, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
2 locks held by syz-executor/6373:
#0:
ffff8880202bfd18
(
&disk->open_mutex
){+.+.}-{3:3}
, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
#1:
ffff88814732a468
(
&lo->lo_mutex
){+.+.}-{3:3}
, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366
1 lock held by syz.5.650/7364:
#0:
ffff88802c79e0e0
(
&type->s_umount_key
#53
){++++}-{3:3}
, at: iterate_supers+0xa4/0x1d0 fs/super.c:716
2 locks held by syz-executor/7596:
#0:
ffff88802ad4e0e0
(
&type->s_umount_key#53){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
#1: ffffffff8c1211e8
(
rcu_state.exp_mutex
){+.+.}-{3:3}
, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
, at: synchronize_rcu_expedited+0x320/0x6b0 kernel/rcu/tree_exp.h:845
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4285 Comm: kworker/1:8 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: xfs-buf/loop0 xfs_buf_ioend_work
RIP: 0010:hlist_move_list include/linux/list.h:984 [inline]
RIP: 0010:collect_expired_timers kernel/time/timer.c:1517 [inline]
RIP: 0010:__run_timers+0x2b9/0x7c0 kernel/time/timer.c:1753
Code: 24 68 4c 8d 34 d8 4d 89 f5 49 c1 ed 03 48 b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 74 08 4c 89 f7 e8 da d0 54 00 49 8b 1e <48> 8b 14 24 48 89 d0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80
RSP: 0018:ffffc90000dd0ca0 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff888061562c90 RCX: ffff88807e498000
RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc90000dd0df0 R08: dffffc0000000000 R09: ffffed1017225026
R10: ffffed1017225026 R11: 1ffff11017225025 R12: 00000000200000fe
R13: 1ffff110172250aa R14: ffff8880b9128550 R15: 0000000000000040
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9297352e9c CR3: 000000007e2f7000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
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_trylock_spinning+0x2cd/0x350 kernel/printk/printk.c:1909
Code: 85 db 74 9d e8 64 a2 18 00 fb 31 c0 eb 48 e8 5a a2 18 00 e8 25 44 4a 08 48 85 db 74 d1 e8 4b a2 18 00 fb 48 c7 c7 a0 12 11 8c <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 68 c6 29 5f
RSP: 0018:ffffc9000337f840 EFLAGS: 00000293
RAX: ffffffff815f29c5 RBX: 0000000000000200 RCX: ffff88807e498000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c1112a0
RBP: ffffc9000337f910 R08: dffffc0000000000 R09: fffffbfff1ff7c3c
R10: fffffbfff1ff7c3c R11: 1ffffffff1ff7c3b R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffff9200066ff08
vprintk_emit+0xa7/0x150 kernel/printk/printk.c:2273
_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_allocbt_read_verify+0x53/0xd0 fs/xfs/libxfs/xfs_alloc_btree.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