rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4541/1:b..l
(detected by 1, t=10503 jiffies, g=6457, q=77)
task:syz.4.91 state:R running task stack:27648 pid: 4541 ppid: 4192 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
preempt_schedule_notrace+0xca/0x110 kernel/sched/core.c:6650
preempt_schedule_notrace_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
rcu_is_watching+0x72/0xa0 kernel/rcu/tree.c:1124
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0xcd/0x3f0 kernel/locking/lockdep.c:5594
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
rcu_read_lock include/linux/rcupdate.h:740 [inline]
nl80211_netlink_notify+0x6b/0x7c0 net/wireless/nl80211.c:18042
notifier_call_chain kernel/notifier.c:83 [inline]
blocking_notifier_call_chain+0x103/0x1b0 kernel/notifier.c:318
netlink_release+0xf13/0x1790 net/netlink/af_netlink.c:766
__sock_release net/socket.c:651 [inline]
sock_close+0xd5/0x240 net/socket.c:1346
__fput+0x234/0x930 fs/file_table.c:311
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: 0033:0x7fd8e79db749
RSP: 002b:00007ffc5ac57e68 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 0000000000010570 RCX: 00007fd8e79db749
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fd8e7c33da0 R08: 0000000000000001 R09: 0000000f5ac5815f
R10: 0000001b31520000 R11: 0000000000000246 R12: 00007fd8e7c31fac
R13: 00007fd8e7c31fa0 R14: ffffffffffffffff R15: 00007ffc5ac57f80
rcu: rcu_preempt kthread timer wakeup didn't happen for 10526 jiffies! g6457 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=2365
rcu: rcu_preempt kthread starved for 10529 jiffies! g6457 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
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:I stack:28064 pid: 15 ppid: 2 flags:0x00004000
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_timeout+0x15c/0x280 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
kthread+0x436/0x520 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 1
CPU: 1 PID: 4529 Comm: syz.1.85 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_single_cpu_backtrace include/linux/nmi.h:166 [inline]
rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
rcu_pending kernel/rcu/tree.c:3936 [inline]
rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:1818
tick_sched_handle kernel/time/tick-sched.c:254 [inline]
tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
__run_hrtimer kernel/time/hrtimer.c:1685 [inline]
__hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1749
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:raw_spin_rq_unlock_irq+0x13/0x90 kernel/sched/sched.h:1339
Code: c0 48 8b 3c 24 e8 fd be 68 00 eb b5 66 2e 0f 1f 84 00 00 00 00 00 90 41 57 41 56 53 eb 11 e8 14 66 5f 08 e8 af 74 2a 00 fb 5b <41> 5e 41 5f c3 49 be 00 00 00 00 00 fc ff df 49 89 ff 48 8d 9f 58
RSP: 0018:ffffc9000345f848 EFLAGS: 00000286
RAX: a739cf6d6c139e00 RBX: ffff8880b913a340 RCX: a739cf6d6c139e00
RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580
RBP: ffffc9000345fa40 R08: dffffc0000000000 R09: ffffed1017207469
R10: ffffed1017207469 R11: 1ffff11017207468 R12: 1ffff110172275ab
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff8880b913b088
__schedule+0x1464/0x4390 kernel/sched/core.c:6401
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
freezable_schedule include/linux/freezer.h:172 [inline]
futex_wait_queue_me+0x22d/0x440 kernel/futex/core.c:2863
futex_wait+0x202/0x5c0 kernel/futex/core.c:2964
do_futex+0xd1c/0x1240 kernel/futex/core.c:3982
__do_sys_futex kernel/futex/core.c:4059 [inline]
__se_sys_futex+0x3a3/0x430 kernel/futex/core.c:4040
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: 0033:0x7f52a0ea6749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f529f10d0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f52a10fcfa8 RCX: 00007f52a0ea6749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f52a10fcfa8
RBP: 00007f52a10fcfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f52a10fd038 R14: 00007ffd6a5df880 R15: 00007ffd6a5df968
sched: RT throttling activated