rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=02c4/1/0x4000000000000000 softirq=19507/19507 fqs=3
rcu: (detected by 1, t=10505 jiffies, g=21013, q=343 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_power_efficient gc_worker
RIP: 0010:__lock_acquire+0x2ec/0x2de0 kernel/locking/lockdep.c:-1
Code: 8e 44 89 3c 24 49 89 f7 4c 89 f6 e8 1e a7 79 03 4c 89 fe 44 8b 3c 24 48 83 bc 24 20 01 00 00 00 0f 85 ad fe ff ff 44 89 3c 24 <44> 89 6c 24 40 89 6c 24 28 8b bc 24 48 01 00 00 8b ac 24 38 01 00
RSP: 0018:ffffc90000007b50 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff943af4d0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9abc0c40
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffc90000007d58 R11: fffff52000000fad R12: 0000000000000000
R13: 0000000000000001 R14: 0000000000000004 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124cdc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f550ead4ff8 CR3: 00000000715d0000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:155 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:181
debug_object_deactivate+0x9a/0x250 lib/debugobjects.c:936
debug_hrtimer_deactivate kernel/time/hrtimer.c:491 [inline]
__run_hrtimer kernel/time/hrtimer.c:2042 [inline]
__hrtimer_run_queues+0x239/0xa10 kernel/time/hrtimer.c:2131
hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2250
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:seqcount_lockdep_reader_access+0xed/0x100 include/linux/seqlock.h:76
Code: 00 75 11 e8 45 5a c8 f7 4d 85 f6 75 16 e8 3b 5a c8 f7 eb 15 e8 34 5a c8 f7 e8 9f 41 e6 01 4d 85 f6 74 ea e8 25 5a c8 f7 fb 5b <41> 5e c3 cc cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90
RSP: 0018:ffffc900000e7970 EFLAGS: 00000293
RAX: ffffffff89ff93eb RBX: 0000000000000001 RCX: ffff88801defddc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900000e7ad0 R08: ffffffff9079a07f R09: 1ffffffff20f340f
R10: dffffc0000000000 R11: fffffbfff20f3410 R12: dffffc0000000000
R13: ffffffff818fa5ea R14: 0000000000000200 R15: 000000000000f4e1
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:348 [inline]
gc_worker+0x31b/0x1890 net/netfilter/nf_conntrack_core.c:1532
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 10065 jiffies! g21013 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:R running task stack:27744 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7376
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 6110 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:csd_lock_wait kernel/smp.c:363 [inline]
RIP: 0010:csd_lock kernel/smp.c:396 [inline]
RIP: 0010:smp_call_function_many_cond+0x628/0x1500 kernel/smp.c:944
Code: 00 44 8b 3b 44 89 fe 83 e6 01 31 ff e8 01 59 0c 00 41 83 e7 01 75 07 e8 f6 53 0c 00 eb 3f f3 90 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 04 04 84 c0 75 0f f7 03 01 00 00 00 74 1d e8 d2 53 0c 00
RSP: 0018:ffffc90002e57560 EFLAGS: 00000293
RAX: dffffc0000000000 RBX: ffff8880b8643708 RCX: ffff8880293bddc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90002e576b0 R08: ffff8880293bf35f R09: 1ffff11005277e6b
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff110170c86e1
R13: 0000000000000000 R14: ffff8880b8643700 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124ddc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560c07712a38 CR3: 000000007546a000 CR4: 00000000003526f0
Call Trace:
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x8ff/0x1090 arch/x86/mm/tlb.c:1435
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline]
tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:423
tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:549
free_ldt_pgtables+0x192/0x360 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:229 [inline]
exit_mmap+0x1bf/0x9f0 mm/mmap.c:1300
__mmput+0x118/0x420 kernel/fork.c:1193
exit_mm+0x18e/0x240 kernel/exit.c:592
do_exit+0x6cd/0x2360 kernel/exit.c:974
do_group_exit+0x22d/0x2f0 kernel/exit.c:1129
__do_sys_exit_group kernel/exit.c:1140 [inline]
__se_sys_exit_group kernel/exit.c:1138 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1138
x64_sys_call+0x18c6/0x18d0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f17e28f16c5
Code: Unable to access opcode bytes at 0x7f17e28f169b.
RSP: 002b:00007ffeb08ab768 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000560c0772c4d0 RCX: 00007f17e28f16c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 0000560c07709910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeb08ab7b0 R14: 0000000000000000 R15: 0000000000000000