rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=3314/1/0x4000000000000000 softirq=40422/40426 fqs=9
	(t=10501 jiffies g=52757 q=1425 ncpus=2)
rcu: rcu_preempt kthread starved for 10484 jiffies! g52757 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:26864 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </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: 9481 Comm: syz.8.1090 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:preempt_count_sub+0xe7/0x160 kernel/sched/core.c:5738
Code: c0 75 70 83 3d a1 0b c7 0c 00 75 98 48 c7 c7 e0 a1 8b 8a 48 c7 c6 c0 a2 8b 8a e8 64 f8 f4 ff 0f 0b eb 81 48 c7 c1 40 a1 bf 96 <80> e1 07 80 c1 03 38 c1 0f 8c 2e ff ff ff 89 fd 48 c7 c7 40 a1 bf
RSP: 0018:ffffc900001e0c08 EFLAGS: 00000002
RAX: 0000000000000004 RBX: dffffc0000000000 RCX: ffffffff96bfa140
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffffc900001e0cb8 R08: ffff8880763f2023 R09: 1ffff1100ec7e404
R10: dffffc0000000000 R11: ffffed100ec7e405 R12: dffffc0000000000
R13: 1ffff1100ec7e412 R14: ffff8880763f2020 R15: 1ffff9200003c184
FS:  00007fd45d1b96c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 0000000056c28000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0xc1/0x120 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 unlock_timer kernel/time/posix-timers.c:172 [inline]
 posix_timer_fn+0x2dd/0x3d0 kernel/time/posix-timers.c:433
 __run_hrtimer kernel/time/hrtimer.c:1747 [inline]
 __hrtimer_run_queues+0x560/0xd70 kernel/time/hrtimer.c:1811
 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [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 ae 54 2e f7 48 89 df e8 f6 1c 2f f7 e8 71 6d 52 f7 fb bf 01 00 00 00 <e8> 96 7d 22 f7 65 8b 05 57 01 cc 75 85 c0 74 02 5b c3 e8 a4 15 ca
RSP: 0018:ffffc90004fafb98 EFLAGS: 00000282
RAX: ff15e7636ab52c00 RBX: ffff8880783f0000 RCX: ff15e7636ab52c00
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: 0000000000000001
RBP: ffff8880783f0498 R08: ffff8880783f0003 R09: 1ffff1100f07e000
R10: dffffc0000000000 R11: ffffed100f07e001 R12: 1ffff1100f07e093
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1163/0x1350 kernel/signal.c:2874
 arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd45c39aeb7
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:00007fd45d1b90e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007fd45c615fa8 RCX: 00007fd45c39aeb9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd45c615fa8
RBP: 00007fd45c615fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd45c616038 R14: 00007ffcd50d8ce0 R15: 00007ffcd50d8dc8
 </TASK>
CPU: 0 PID: 9458 Comm: syz.1.1184 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [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 ae 54 2e f7 48 89 df e8 f6 1c 2f f7 e8 71 6d 52 f7 fb bf 01 00 00 00 <e8> 96 7d 22 f7 65 8b 05 57 01 cc 75 85 c0 74 02 5b c3 e8 a4 15 ca
RSP: 0018:ffffc9000487fb98 EFLAGS: 00000282
RAX: 43cc250de14d0e00 RBX: ffff8880783f40c0 RCX: 43cc250de14d0e00
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: 0000000000000001
RBP: ffff8880783f4558 R08: ffff8880783f40c3 R09: 1ffff1100f07e818
R10: dffffc0000000000 R11: ffffed100f07e819 R12: 1ffff1100f07e8ab
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
FS:  000055557a92d500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556a9597d0 CR3: 000000007ca51000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1163/0x1350 kernel/signal.c:2874
 arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f519d26b47f
Code: 48 39 f2 73 13 66 0f 1f 44 00 00 48 8b 70 f8 48 83 e8 08 48 39 f2 72 f3 48 39 c3 73 3e 48 89 33 48 89 c6 48 83 c3 08 48 89 08 <48> 8b 0b 48 8b 55 00 eb c0 48 39 f2 72 a4 48 39 f0 0f 83 c0 00 00
RSP: 002b:00007ffccaa9ee80 EFLAGS: 00000216
RAX: 00007f519ca47e98 RBX: 00007f519ca42ca0 RCX: ffffffff84821a1b
RDX: ffffffff84821a1b RSI: 00007f519ca47e98 RDI: 00007f519ca4a240
RBP: 00007f519ca3ea80 R08: 00007f519d600000 R09: 00007f519d616128
R10: 0000000000000003 R11: 0000000000000016 R12: 00007f519ca55a00
R13: 000000000000001a R14: 0000000000002df0 R15: 0000000000000003
 </TASK>