rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...0: (1 GPs behind) idle=33f/1/0x4000000000000000 softirq=11569/11571 fqs=2
(detected by 0, t=11070 jiffies, g=14241, q=1177)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4272 Comm: kworker/1:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_power_efficient gc_worker
RIP: 0010:check_preemption_disabled+0x3/0x110 lib/smp_processor_id.c:13
Code: c7 c7 20 e9 32 8a e8 2c 01 00 00 65 ff 0d c1 7a 46 76 5b c3 00 00 cc 48 c7 c7 a0 fd 79 8a 48 c7 c6 e0 fd 79 8a eb 00 55 41 57 <41> 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65
RSP: 0018:ffffc90000dd0b68 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888028fdd940 RCX: 1364940ff6556d00
RDX: 0000000000000000 RSI: ffffffff8a2b3600 RDI: ffffffff8a79fe00
RBP: ffffc90000dd0c90 R08: ffffffff8d89f02f R09: 1ffffffff1b13e05
R10: dffffc0000000000 R11: fffffbfff1b13e06 R12: 1ffff920001ba17c
R13: dffffc0000000000 R14: ffff888028fde42c R15: 0000000000000046
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffffde8b0b8 CR3: 000000002adf9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lockdep_recursion_inc kernel/locking/lockdep.c:431 [inline]
lock_release+0x15d/0x8a0 kernel/locking/lockdep.c:5642
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline]
_raw_spin_unlock_irqrestore+0x6d/0x120 kernel/locking/spinlock.c:194
__run_hrtimer kernel/time/hrtimer.c:1681 [inline]
__hrtimer_run_queues+0x3fd/0xb70 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:seqcount_lockdep_reader_access+0x196/0x1d0 include/linux/seqlock.h:106
Code: f9 4d 85 e4 75 16 e8 99 ca 54 f9 eb 15 e8 92 ca 54 f9 e8 ad 5f 98 01 4d 85 e4 74 ea e8 83 ca 54 f9 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc9000318fa20 EFLAGS: 00000293
RAX: ffffffff88246a0d RBX: 0000000000000000 RCX: ffff888028fdd940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000318fad0 R08: ffffffff901d515f R09: 1ffffffff203aa2b
R10: dffffc0000000000 R11: fffffbfff203aa2c R12: 0000000000000200
R13: ffff888023054180 R14: 1ffff92000631f44 R15: dffffc0000000000
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:338 [inline]
gc_worker+0x2e2/0x1390 net/netfilter/nf_conntrack_core.c:1472
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: rcu_preempt kthread timer wakeup didn't happen for 5389 jiffies! g14241 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=8478
rcu: rcu_preempt kthread starved for 5390 jiffies! g14241 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27800 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x9b/0x370 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 0
CPU: 0 PID: 4869 Comm: syz-execprog Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 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+0x1110/0x1270 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+0x843/0x1120 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:2021
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+0x4b4/0xb70 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+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0033:0x43652f
Code: 0f b6 14 11 85 d2 75 09 49 8d 50 40 49 89 d0 eb dc 45 31 c9 eb 09 49 ff c1 d1 ea 49 83 c0 08 49 83 f9 08 7d c8 4c 39 c3 76 c3 <0f> ba e2 00 73 e6 4d 8d 14 00 4d 8b 12 0f 1f 40 00 4d 85 d2 74 d6
RSP: 002b:000028c323f8ddb8 EFLAGS: 00000216
RAX: 0000000003e2c9e0 RBX: 0000000000040000 RCX: 00007f7369617000
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000028c322bcb260
RBP: 000028c323f8de08 R08: 0000000000032778 R09: 0000000000000007
R10: 0000000000000000 R11: 0000000000006c04 R12: 000028c323f8ded8
R13: 0000000000000000 R14: 000028c3240ec780 R15: 0000000000000005