ODEBUG: Out of memory. ODEBUG disabled
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 1-...!: (10497 ticks this GP) idle=a0d/0/0x1 softirq=13192/13192 fqs=0
(t=10500 jiffies g=16253 q=1661)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g16253 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=9854
rcu: rcu_preempt kthread starved for 10500 jiffies! g16253 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:28016 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:1914
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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5685 Comm: syz.4.305 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__unsafe_setup_sigcontext arch/x86/kernel/signal.c:174 [inline]
RIP: 0010:__setup_rt_frame arch/x86/kernel/signal.c:485 [inline]
RIP: 0010:setup_rt_frame arch/x86/kernel/signal.c:780 [inline]
RIP: 0010:handle_signal arch/x86/kernel/signal.c:824 [inline]
RIP: 0010:arch_do_signal_or_restart+0xb74/0x12c0 arch/x86/kernel/signal.c:869
Code: 94 00 48 8b 03 49 89 47 68 48 8b 44 24 08 4c 8d b0 f0 18 00 00 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 4c 89 f7 e8 c2 51 94 00 49 8b 06 49 89 87 d0 00 00 00 48 8b
RSP: 0018:ffffc900047afcc0 EFLAGS: 00040246
RAX: 1ffff110030b86d6 RBX: ffffc900047aff58 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880185c2730
RBP: ffffc900047afec0 R08: 0000000000000000 R09: 1ffffffff17c6065
R10: dffffc0000000000 R11: fffffbfff17c6066 R12: 0000000000000000
R13: ffff8880185c1dc0 R14: ffff8880185c36b0 R15: 00007ffe5d458b38
FS: 00005555748a3500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 0000000069233000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd9ae6ceeb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe5d4590c8 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 0000000000030521 RCX: 00007fd9ae6ceeb9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd9ae949fac
RBP: 0000000000000fd2 R08: 00369c00927b1052 R09: 0000000000000000
R10: 00007ffe5d4591d0 R11: 0000000000000246 R12: 00007ffe5d4591f0
R13: 00007fd9ae949fac R14: 00000000000314f3 R15: 00007ffe5d4591d0
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349
print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633
check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
rcu_pending kernel/rcu/tree.c:3936 [inline]
rcu_sched_clock_irq+0x6ea/0x1120 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+0x4ad/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:default_idle+0xb/0x10 arch/x86/kernel/process.c:730
Code: b7 48 89 df e8 f6 ea f8 f7 eb ad e8 8f af f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d b7 96 60 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffc90000d67d48 EFLAGS: 000002c2
RAX: b1427b72c4873300 RBX: ffff88813fe68000 RCX: b1427b72c4873300
RDX: 0000000000000001 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f780
RBP: ffffc90000d67e80 R08: ffff8880b913b30b R09: 1ffff11017227661
R10: dffffc0000000000 R11: ffffed1017227662 R12: 1ffff11027fcd000
R13: dffffc0000000000 R14: 0000000000000001 R15: 1ffff920001acfb4
default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
cpuidle_idle_call kernel/sched/idle.c:194 [inline]
do_idle+0x21f/0x580 kernel/sched/idle.c:306
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
start_secondary+0x330/0x430 arch/x86/kernel/smpboot.c:281
secondary_startup_64_no_verify+0xb1/0xbb