rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=5e1/1/0x4000000000000000 softirq=25452/25453 fqs=7
(detected by 0, t=10506 jiffies, g=35209, q=390)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 9832 Comm: syz.1.1512 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:enqueue_hrtimer+0xdb/0x370 kernel/time/hrtimer.c:1070
Code: 4d 89 f5 49 c1 ed 03 43 80 7c 25 00 00 74 08 4c 89 f7 e8 18 4c 54 00 4d 8b 3e 49 83 c7 4c 4c 89 f8 48 c1 e8 03 42 0f b6 04 20 <84> c0 0f 85 ea 00 00 00 41 0f b6 2f 89 ee 83 e6 10 31 ff e8 3d e6
RSP: 0018:ffffc90000dd0ce8 EFLAGS: 00000803
RAX: 0000000000000000 RBX: ffff88805a822340 RCX: ffff88801ff50000
RDX: 0000000000010000 RSI: ffffffff8a59a4a0 RDI: ffffffff8a59a460
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1ad32b6
R10: fffffbfff1ad32b6 R11: 1ffffffff1ad32b5 R12: dffffc0000000000
R13: 1ffff11017225468 R14: ffff8880b912a340 R15: ffff8880b912a28c
FS: 00007fee3df5c6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c38411e CR3: 00000000653c2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__run_hrtimer kernel/time/hrtimer.c:1702 [inline]
__hrtimer_run_queues+0x65a/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_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194
Code: 74 05 e8 ae 4b cb f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 36 d5 9e f7 65 8b 05 17 d3 4f 76 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc900030af5c0 EFLAGS: 00000206
RAX: afcc25a155041c00 RBX: 0000000000000a06 RCX: afcc25a155041c00
RDX: dffffc0000000000 RSI: ffffffff8a0b1820 RDI: 0000000000000001
RBP: ffffc900030af650 R08: dffffc0000000000 R09: fffffbfff1ff7a2f
R10: fffffbfff1ff7a2f R11: 1ffffffff1ff7a2e R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88801f790ec0 R15: 1ffff92000615eb8
spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
__wake_up_common_lock kernel/sched/wait.c:140 [inline]
__wake_up_sync_key+0x11b/0x180 kernel/sched/wait.c:205
__unix_dgram_recvmsg+0x497/0xd50 net/unix/af_unix.c:2342
____sys_recvmsg+0x291/0x580 net/socket.c:-1
___sys_recvmsg+0x1af/0x4f0 net/socket.c:2697
do_recvmmsg+0x344/0x7a0 net/socket.c:2791
__sys_recvmmsg net/socket.c:2870 [inline]
__do_sys_recvmmsg net/socket.c:2893 [inline]
__se_sys_recvmmsg net/socket.c:2886 [inline]
__x64_sys_recvmmsg+0x18d/0x240 net/socket.c:2886
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: 0033:0x7fee3fd15ec9
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:00007fee3df5c038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fee3ff6d090 RCX: 00007fee3fd15ec9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007fee3fd98f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fee3ff6d128 R14: 00007fee3ff6d090 R15: 00007ffdc648be98
rcu: rcu_preempt kthread starved for 10470 jiffies! g35209 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:27848 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 0
CPU: 0 PID: 9842 Comm: syz.0.1516 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xb88/0xd70 kernel/smp.c:969
Code: b6 44 05 00 84 c0 0f 85 9d 00 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 66 49 0b 00 83 e3 01 75 07 e8 fc 45 0b 00 eb 43 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 11 41 f7
RSP: 0018:ffffc900040bfaa0 EFLAGS: 00000246
RAX: ffffffff816c847b RBX: 0000000000000001 RCX: 0000000000080000
RDX: ffffc90005c41000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc900040bfbe0 R08: dffffc0000000000 R09: fffffbfff1ff7a19
R10: fffffbfff1ff7a19 R11: 1ffffffff1ff7a18 R12: ffff8880b91405c8
R13: 1ffff110172280b9 R14: ffff8880b903b3c0 R15: 0000000000000001
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:1442 [inline]
text_poke_bp_batch+0x2a9/0x7c0 arch/x86/kernel/alternative.c:1642
text_poke_flush arch/x86/kernel/alternative.c:1833 [inline]
text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1840
arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
static_key_slow_inc_cpuslocked+0x121/0x210 kernel/jump_label.c:144
static_key_slow_inc+0x16/0x20 kernel/jump_label.c:159
bpf_enable_runtime_stats kernel/bpf/syscall.c:4504 [inline]
bpf_enable_stats+0x101/0x140 kernel/bpf/syscall.c:4523
__sys_bpf+0x571/0x670 kernel/bpf/syscall.c:4740
__do_sys_bpf kernel/bpf/syscall.c:4761 [inline]
__se_sys_bpf kernel/bpf/syscall.c:4759 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759
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: 0033:0x7ff220db5ec9
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:00007ff21f01d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007ff22100cfa0 RCX: 00007ff220db5ec9
RDX: 0000000000000004 RSI: 0000200000000200 RDI: 0000000000000020
RBP: 00007ff220e38f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff22100d038 R14: 00007ff22100cfa0 R15: 00007fff93f78da8