INFO: task syz-executor:5773 blocked for more than 143 seconds.
Not tainted 6.6.95-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21736 pid:5773 ppid:1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x14e2/0x4580 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
sync_filesystem+0x171/0x220 fs/sync.c:64
generic_shutdown_super+0x6f/0x2b0 fs/super.c:666
kill_block_super+0x44/0x90 fs/super.c:1660
deactivate_locked_super+0x97/0x100 fs/super.c:481
cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
task_work_run+0x1ce/0x250 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x90b/0x23c0 kernel/exit.c:883
do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
__do_sys_exit_group kernel/exit.c:1035 [inline]
__se_sys_exit_group kernel/exit.c:1033 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd09498e929
RSP: 002b:00007ffc55300c28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fd094a109a9 RCX: 00007fd09498e929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000027 R08: 00007ffc552fe9c6 R09: 00007ffc55301ee0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc55301ee0
R13: 00007fd094a10925 R14: 000055557bb744a8 R15: 00007ffc553040a0
Showing all locks held in the system:
2 locks held by kworker/u4:0/11:
#0: ffff88801ca4bd38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff88801ca4bd38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc90000107d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90000107d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
1 lock held by khungtaskd/29:
#0: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
5 locks held by kworker/u4:4/61:
2 locks held by getty/5538:
#0: ffff88807fc680a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000326b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
2 locks held by syz-executor/5773:
#0: ffff8880737c00e0 (&type->s_umount_key#79){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff8880737c00e0 (&type->s_umount_key#79){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff8880737c00e0 (&type->s_umount_key#79){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1: ffff88802154e7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline]
#1: ffff88802154e7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1a0/0x9e0 fs/fs-writeback.c:2759
1 lock held by segctord/6549:
#0: ffff8880b8e3c458 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558
2 locks held by kworker/u4:27/7040:
3 locks held by syz.2.891/8645:
#0: ffff8880b8f3c458 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558
#1: ffff8880b8f288c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39c/0x6d0 kernel/sched/psi.c:998
#2: ffff88802431cc68 (&(&sig->stats_lock)->lock){....}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff88802431cc68 (&(&sig->stats_lock)->lock){....}-{2:2}, at: write_seqlock include/linux/seqlock.h:933 [inline]
#2: ffff88802431cc68 (&(&sig->stats_lock)->lock){....}-{2:2}, at: __exit_signal kernel/exit.c:186 [inline]
#2: ffff88802431cc68 (&(&sig->stats_lock)->lock){....}-{2:2}, at: release_task+0x7cf/0x1610 kernel/exit.c:256
6 locks held by syz.2.891/8653:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.6.95-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5122 Comm: syslogd Not tainted 6.6.95-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__lock_acquire+0x1c04/0x7c80 kernel/locking/lockdep.c:5168
Code: 17 00 00 00 00 42 c6 44 00 1b 00 65 48 8b 04 25 28 00 00 00 48 3b 84 24 00 02 00 00 0f 85 de 4b 00 00 44 89 f0 48 8d 65 d8 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 31 db e9 63 f6 ff ff 48 c7 c7 60 b9
RSP: 0018:ffffc900032573c8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81671100
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90d85520
RBP: ffffc900032573e8 R08: dffffc0000000000 R09: 1ffffffff21b0aa4
R10: dffffc0000000000 R11: fffffbfff21b0aa5 R12: 21172683b190bb39
R13: ffff88807f3c5a00 R14: 0000000000000001 R15: ffff88807f3c6500
FS: 00007faab91f5c80(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1024380ab8 CR3: 0000000030abd000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
finish_lock_switch kernel/sched/core.c:5133 [inline]
finish_task_switch+0x19f/0x920 kernel/sched/core.c:5253
context_switch kernel/sched/core.c:5384 [inline]
__schedule+0x14ea/0x4580 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_timeout+0x9b/0x280 kernel/time/timer.c:2143
__skb_wait_for_more_packets+0x39e/0x580 net/core/datagram.c:120
__unix_dgram_recvmsg+0x286/0xd60 net/unix/af_unix.c:2375
sock_recvmsg_nosec net/socket.c:1046 [inline]
sock_recvmsg net/socket.c:1068 [inline]
sock_read_iter+0x2b7/0x3b0 net/socket.c:1138
call_read_iter include/linux/fs.h:2012 [inline]
new_sync_read fs/read_write.c:389 [inline]
vfs_read+0x431/0x920 fs/read_write.c:470
ksys_read+0x147/0x250 fs/read_write.c:613
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7faab9345407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffc3dbb0880 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007faab91f5c80 RCX: 00007faab9345407
RDX: 00000000000000ff RSI: 000055a2cc9b2950 RDI: 0000000000000000
RBP: 000055a2cc9b2910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055a2cc9b299c
R13: 0000000000000000 R14: 000055a2cc9b2950 R15: 000055a2be1c3d98