INFO: task syz.5.13912:2849 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.13912 state:D stack:25160 pid:2849 tgid:2849 ppid:19078 task_flags:0x400040 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
request_wait_answer fs/fuse/dev.c:585 [inline]
__fuse_request_send fs/fuse/dev.c:599 [inline]
__fuse_simple_request+0x11d2/0x1bb0 fs/fuse/dev.c:693
fuse_simple_request fs/fuse/fuse_i.h:1250 [inline]
fuse_flush+0x5dd/0x810 fs/fuse/file.c:482
filp_flush+0xc0/0x190 fs/open.c:1549
filp_close+0x1d/0x40 fs/open.c:1562
__range_close fs/file.c:767 [inline]
__do_sys_close_range fs/file.c:826 [inline]
__se_sys_close_range+0x35c/0x650 fs/file.c:790
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc0fbbfefc9
RSP: 002b:00007ffedca8d408 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00000000000ae59e RCX: 00007fc0fbbfefc9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fc0fbe57da0 R08: 0000000000000001 R09: 00000009dca8d6ff
R10: 0000001b33120000 R11: 0000000000000246 R12: 00007fc0fbe5609c
R13: 00007fc0fbe56090 R14: ffffffffffffffff R15: 00007ffedca8d520
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d5aa800 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5aa800 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5aa800 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/59:
2 locks held by getty/5559:
#0: ffff88823bf340a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000421b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
6 locks held by syz-executor/6412:
5 locks held by syz-executor/8600:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 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: 59 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: bat_events batadv_dat_purge
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3801 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3821 [inline]
RIP: 0010:validate_chain+0x1ea/0x2140 kernel/locking/lockdep.c:3876
Code: 00 74 c8 e9 8d 00 00 00 48 c7 c7 d0 ab 47 8d 4c 89 fe e8 69 a4 15 03 48 8b 14 24 eb c9 48 8b 48 18 4c 39 f9 0f 84 b2 00 00 00 <48> 8b 40 08 48 85 c0 0f 84 c2 fe ff ff 48 83 c0 f8 75 e0 e9 b7 fe
RSP: 0018:ffffc9000125f638 EFLAGS: 00000012
RAX: ffffffff930b0bb0 RBX: 0000000000058360 RCX: 7e5f7fa14d541a40
RDX: 0000000000000000 RSI: ffff8880197a4828 RDI: ffff8880197a3c00
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8ac2aaca
R10: dffffc0000000000 R11: fffffbfff1dac5ef R12: 0000000000000000
R13: ffff8880197a4760 R14: ffff8880197a4828 R15: 0823264d3fde25a2
FS: 0000000000000000(0000) GS:ffff888126df9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe02da9cd8 CR3: 00000000337ba000 CR4: 00000000003526f0
Call Trace:
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
rtlock_slowlock kernel/locking/rtmutex.c:1894 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x14a/0x3e0 kernel/locking/spinlock_rt.c:57
spin_lock_bh include/linux/spinlock_rt.h:88 [inline]
__batadv_dat_purge+0x131/0x400 net/batman-adv/distributed-arp-table.c:173
batadv_dat_purge+0x20/0x70 net/batman-adv/distributed-arp-table.c:204
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
vkms_vblank_simulate: vblank timer overrun