rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-....: (1 ticks this GP) idle=0b1c/1/0x4000000000000000 softirq=66149/66149 fqs=2
rcu: (detected by 0, t=10505 jiffies, g=69593, q=720 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5752 Comm: kworker/1:6 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: events_power_efficient gc_worker
RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5620 [inline]
RIP: 0010:lock_is_held_type+0x8b/0x150 kernel/locking/lockdep.c:5982
Code: 41 83 bd a0 0b 00 00 00 7e 48 4c 89 eb 48 81 c3 b0 0b 00 00 45 31 ff 49 83 ff 31 73 24 48 89 df 4c 89 f6 e8 f7 01 00 00 85 c0 <75> 2a 49 ff c7 49 63 85 a0 0b 00 00 48 83 c3 28 49 39 c7 7c d8 eb
RSP: 0018:ffffc90000a18d88 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888068804a58 RCX: 0000000001000001
RDX: 0000000001000001 RSI: ffff8880b8728298 RDI: ffff888068804a58
RBP: 00000000ffffffff R08: 0000000001000001 R09: ffff88807cb14308
R10: dffffc0000000000 R11: ffffed100f962863 R12: 0000000000000046
R13: ffff888068803e80 R14: ffff8880b8728298 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124dd8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fca77de4f88 CR3: 000000001206d000 CR4: 0000000000350ef0
Call Trace:
lock_is_held include/linux/lockdep.h:249 [inline]
__run_hrtimer kernel/time/hrtimer.c:2033 [inline]
__hrtimer_run_queues+0x20b/0xa10 kernel/time/hrtimer.c:2124
hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2243
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 a5 22 c8 f7 4d 85 f6 75 16 e8 9b 22 c8 f7 eb 15 e8 94 22 c8 f7 e8 2f ac e4 01 4d 85 f6 74 ea e8 85 22 c8 f7 fb 5b <41> 5e e9 67 a8 10 f7 cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90
RSP: 0018:ffffc90002567970 EFLAGS: 00000293
RAX: ffffffff89ff989b RBX: 0000000000000001 RCX: ffff888068803e80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90002567ad0 R08: ffffffff907a157f R09: 1ffffffff20f42af
R10: dffffc0000000000 R11: fffffbfff20f42b0 R12: dffffc0000000000
R13: ffffffff818f981a R14: 0000000000000200 R15: 000000000000d3a9
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:343 [inline]
gc_worker+0x31b/0x1890 net/netfilter/nf_conntrack_core.c:1534
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 815 jiffies! g69593 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5520 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7270
__schedule_loop kernel/sched/core.c:7347 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7362
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: 0 UID: 0 PID: 5777 Comm: kworker/0:6 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: events netstamp_clear
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 51 54 0c 00 41 83 e7 01 75 07 e8 46 4f 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 22 4f 0c 00
RSP: 0018:ffffc90004c77800 EFLAGS: 00000293
RAX: dffffc0000000000 RBX: ffff8880b87414c8 RCX: ffff88802d609f40
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004c77950 R08: ffff88802d60b4df R09: 1ffff11005ac169b
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff110170e8299
R13: 0000000000000001 R14: ffff8880b87414c0 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124cd8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563e82357fd0 CR3: 000000000eb48000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2602 [inline]
smp_text_poke_batch_finish+0x5fd/0x1110 arch/x86/kernel/alternative.c:2812
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240
static_key_disable+0x1a/0x20 kernel/jump_label.c:248
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