rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6499/1:b..l
(detected by 0, t=10503 jiffies, g=21093, q=160)
task:syz.2.900 state:R running task stack:26008 pid: 6499 ppid: 3574 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549
preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
_raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194
spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
__wake_up_common_lock kernel/sched/wait.c:140 [inline]
__wake_up_sync_key+0x121/0x1c0 kernel/sched/wait.c:205
sock_def_readable+0x135/0x240 net/core/sock.c:3092
__netlink_sendskb net/netlink/af_netlink.c:1273 [inline]
netlink_broadcast_deliver net/netlink/af_netlink.c:1405 [inline]
do_one_broadcast net/netlink/af_netlink.c:1490 [inline]
netlink_broadcast_filtered+0xc60/0x11a0 net/netlink/af_netlink.c:1534
netlink_broadcast net/netlink/af_netlink.c:1558 [inline]
nlmsg_multicast include/net/netlink.h:1033 [inline]
nlmsg_notify+0xf7/0x1b0 net/netlink/af_netlink.c:2547
unregister_netdevice_many+0x12e1/0x18f0 net/core/dev.c:11114
unregister_netdevice_queue net/core/dev.c:11027 [inline]
unregister_netdevice include/linux/netdevice.h:3012 [inline]
unregister_netdev+0x19b/0x210 net/core/dev.c:11153
tty_ldisc_kill+0xa6/0x1a0 drivers/tty/tty_ldisc.c:629
tty_ldisc_release+0x19d/0x200 drivers/tty/tty_ldisc.c:803
tty_release_struct+0x27/0xd0 drivers/tty/tty_io.c:1708
tty_release+0xd53/0x1310 drivers/tty/tty_io.c:1880
__fput+0x3fe/0x8e0 fs/file_table.c:280
task_work_run+0x129/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f3b9329ceb9
RSP: 002b:00007ffc958ab818 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f3b9343aa80 RCX: 00007f3b9329ceb9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f3b9343aa80 R08: 00007f3b93425000 R09: 00007ffc958abb0f
R10: 00000000005f998c R11: 0000000000000246 R12: 000000000002070a
R13: 00007ffc958ab920 R14: 0000000000000032 R15: ffffffffffffffff
rcu: rcu_preempt kthread starved for 10501 jiffies! g21093 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:25976 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 5.15.165-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: events fqdir_free_fn
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
rcu_pending kernel/rcu/tree.c:3932 [inline]
rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
update_process_times+0x196/0x200 kernel/time/timer.c:1818
tick_sched_handle kernel/time/tick-sched.c:254 [inline]
tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
__run_hrtimer kernel/time/hrtimer.c:1686 [inline]
__hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
__sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_single+0x292/0x530 kernel/smp.c:758
Code: 0f 85 24 02 00 00 44 8b 6c 24 48 44 89 ee 83 e6 01 31 ff e8 c0 e4 0b 00 41 83 e5 01 75 0a e8 55 e1 0b 00 e9 eb 00 00 00 f3 90 <42> 0f b6 04 23 84 c0 75 15 f7 44 24 48 01 00 00 00 0f 84 cd 00 00
RSP: 0018:ffffc90000cc7a60 EFLAGS: 00000293
RAX: ffffffff8174806e RBX: 1ffff92000198f55 RCX: ffff888017d73b80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000cc7b50 R08: ffffffff81748040 R09: ffffed1017227679
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffc90000cc7aa8 R15: 0000000000000000
rcu_barrier+0x262/0x4e0 kernel/rcu/tree.c:4078
fqdir_free_fn+0x2e/0x130 net/ipv4/inet_fragment.c:163
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287