rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=683/1/0x4000000000000000 softirq=32330/32334 fqs=2 
	(t=10501 jiffies g=39369 q=135)
rcu: rcu_preempt kthread starved for 10498 jiffies! g39369 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:27760 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 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
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10102 Comm: syz.2.1054 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:exit_to_user_mode_prepare+0x1c/0x180 kernel/entry/common.c:207
Code: 5b c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 41 57 41 56 53 49 89 fe 83 3d b5 4a 22 0c 00 74 1a 65 8b 05 68 39 9b 7e 85 c0 75 0f <65> 8b 05 8d 36 9b 7e 85 c0 0f 85 23 01 00 00 e8 70 f9 52 08 65 4c
RSP: 0018:ffffc900033d7ef0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffc900033d7f58 RCX: 0000000000080000
RDX: ffffc90006189000 RSI: 000000000007ffff RDI: ffffc900033d7f58
RBP: ffffc900033d7f48 R08: ffffffff8d8956ef R09: 1ffffffff1b12add
R10: dffffc0000000000 R11: fffffbfff1b12ade R12: 0000000000000000
R13: 0000000000000000 R14: ffffc900033d7f58 R15: 0000000000000027
FS:  00007f1d2815a6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 0000000054926000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __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: 0033:0x7f1d29ef8ad7
Code: 8d 3d 5b 4a 0b 00 e8 58 1d fa ff e8 23 87 00 00 0f 1f 00 b8 68 00 00 00 0f 05 c3 0f 1f 84 00 00 00 00 00 b8 27 00 00 00 0f 05 <c3> 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00
RSP: 002b:00007f1d28159b08 EFLAGS: 00000202 ORIG_RAX: 0000000000000027
RAX: 00000000000001da RBX: 00007f1d28159c70 RCX: 00007f1d29ef8ad7
RDX: 00007f1d28159b40 RSI: 00007f1d28159c70 RDI: 0000000000000021
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007f1d2a17a038 R14: 00007ffc286ebd90 R15: 00007ffc286ebe78
 </TASK>
NMI backtrace for cpu 0
CPU: 0 PID: 10112 Comm: syz.0.1057 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <IRQ>
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 00 00 00 66 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 2e de 99 f7 48 89 df e8 66 b6 9a f7 e8 f1 a4 bb f7 fb bf 01 00 00 00 <e8> 36 bc 8e f7 65 8b 05 b7 d8 3e 76 85 c0 74 02 5b c3 e8 04 e6 3c
RSP: 0018:ffffc90002ebfbc0 EFLAGS: 00000282
RAX: f9efdce56ecd7500 RBX: ffff888065240940 RCX: f9efdce56ecd7500
RDX: dffffc0000000000 RSI: ffffffff8a2b1c00 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffff888065240943 R09: 1ffff1100ca48128
R10: dffffc0000000000 R11: ffffed100ca48129 R12: ffff888065240940
R13: 0000000000000021 R14: dffffc0000000000 R15: 000000001c000004
 spin_unlock_irq include/linux/spinlock.h:414 [inline]
 get_signal+0x11d6/0x12c0 kernel/signal.c:2903
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 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: 0033:0x7f60b6591cb7
Code: 83 c8 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
RSP: 002b:00007f60b47cc0e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f60b680d098 RCX: 00007f60b6591cb9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f60b680d098
RBP: 00007f60b680d090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f60b680d128 R14: 00007ffc39a0bcd0 R15: 00007ffc39a0bdb8
 </TASK>