rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 ticks this GP) idle=6af4/1/0x4000000000000000 softirq=26208/26208 fqs=6
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5833/1:b.el
rcu: (detected by 0, t=10502 jiffies, g=20853, q=533 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6051 Comm: kworker/1:5 Not tainted 6.15.0-syzkaller-09113-g8477ab143069 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_power_efficient gc_worker
RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:473 [inline]
RIP: 0010:lock_acquire+0x13d/0x360 kernel/locking/lockdep.c:5873
Code: 00 6a 00 55 ff 74 24 30 e8 e0 02 00 00 48 83 c4 28 48 c7 c7 0b b6 b5 8d e8 c0 78 c5 09 b8 ff ff ff ff 65 0f c1 05 53 c8 fd 10 <83> f8 01 0f 85 c9 00 00 00 48 c7 44 24 30 00 00 00 00 9c 8f 44 24
RSP: 0000:ffffc90000a08bc0 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 79bbf4b3b505e500
RDX: 0000000000000000 RSI: ffffffff8db5b60b RDI: ffffffff8be26580
RBP: ffffffff898357b4 R08: 0000000000000000 R09: ffffffff898357b4
R10: dffffc0000000000 R11: ffffffff898356f0 R12: 0000000000000000
R13: ffff888011873300 R14: 0000000000000001 R15: 0000000000000046
FS: 0000000000000000(0000) GS:ffff888125d65000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c001caa0a0 CR3: 0000000032b9c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
advance_sched+0xc4/0xc90 net/sched/sch_taprio.c:924
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:seqcount_lockdep_reader_access+0x17e/0x1c0 include/linux/seqlock.h:75
Code: f8 4d 85 e4 75 16 e8 91 08 2c f8 eb 15 e8 8a 08 2c f8 e8 45 51 cf 01 4d 85 e4 74 ea e8 7b 08 2c f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 66 43 c7 44 3e 09 00 00 43 c6 44 3e 0b 00
RSP: 0000:ffffc90003bff860 EFLAGS: 00000293
RAX: ffffffff89943535 RBX: 0000000000000000 RCX: ffff8880259fbc00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003bff910 R08: ffffffff8fa0a8f7 R09: 1ffffffff1f4151e
R10: dffffc0000000000 R11: fffffbfff1f4151f R12: 0000000000000200
R13: ffff888027c8b718 R14: 1ffff9200077ff0c R15: dffffc0000000000
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:333 [inline]
gc_worker+0x308/0x1380 net/netfilter/nf_conntrack_core.c:1537
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:syz-execprog state:R running task stack:25992 pid:5833 tgid:5824 ppid:5823 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5392 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7104
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 fb 87 fd 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0000:ffffc9000436f7b8 EFLAGS: 00000206
RAX: 59c05b485366f100 RBX: 0000000000000000 RCX: 59c05b485366f100
RDX: 0000000000000000 RSI: ffffffff8db5b60b RDI: ffffffff8be26580
RBP: ffffffff82252390 R08: 0000000000000000 R09: ffffffff82252390
R10: dffffc0000000000 R11: ffffed100ec00ac1 R12: 0000000000000002
R13: ffffffff8e13cc80 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
node_is_toptier+0x6c/0x2b0 mm/memory-tiers.c:287
task_numa_fault+0x130/0x40f0 kernel/sched/fair.c:3186
do_numa_page mm/memory.c:-1 [inline]
handle_pte_fault mm/memory.c:6003 [inline]
__handle_mm_fault+0x4744/0x55e0 mm/memory.c:6140
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6309
do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x421aee
RSP: 002b:000000c004043e80 EFLAGS: 00010206
RAX: 000000c001caa0a0 RBX: 000000c001caa0a0 RCX: 000000000000000e
RDX: 0000000000000020 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 000000c004043f00 R08: 000000c001caa0a0 R09: 000000c001caa0a0
R10: 000000c001caa0a0 R11: 0000000000000016 R12: 000000c004043f00
R13: 0000000000000001 R14: 000000c004010a80 R15: 0000000000000001
rcu: rcu_preempt kthread starved for 5547 jiffies! g20853 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:27320 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5392 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
__schedule_loop kernel/sched/core.c:6859 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6874
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 1093 Comm: kworker/u8:6 Not tainted 6.15.0-syzkaller-09113-g8477ab143069 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xe69/0x11c0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 b0 77 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 5b 73 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 40 73 0b
RSP: 0018:ffffc90003a7f6a0 EFLAGS: 00000293
RAX: ffffffff81b4ca70 RBX: ffff8880b863cc00 RCX: ffff888026c61e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003a7f800 R08: ffffffff8fa0a8f7 R09: 1ffffffff1f4151e
R10: dffffc0000000000 R11: fffffbfff1f4151f R12: 1ffff110170e826d
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b8741368
FS: 0000000000000000(0000) GS:ffff888125c65000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555568045c8 CR3: 000000000df36000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2660 [inline]
smp_text_poke_batch_finish+0x5e0/0x1100 arch/x86/kernel/alternative.c:2870
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:850
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245