rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=43d4/1/0x4000000000000000 softirq=27819/27829 fqs=21
	(t=10501 jiffies g=30413 q=233 ncpus=2)
rcu: rcu_preempt kthread starved for 10459 jiffies! g30413 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:27040 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 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: 7843 Comm: syz.8.872 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:check_preemption_disabled+0x0/0x110 lib/smp_processor_id.c:13
Code: c7 80 70 bc 8c 4c 89 f6 e8 dd 26 17 fa e9 6e ff ff ff 00 00 cc cc 00 00 cc cc 48 c7 c7 80 fa de 8a 48 c7 c6 c0 fa de 8a eb 00 <55> 41 57 41 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44
RSP: 0018:ffffc900001e0e58 EFLAGS: 00000006
RAX: ffffffff817473f8 RBX: 0000007c0e8bfd00 RCX: ffff88802630bb80
RDX: 0000000000010000 RSI: ffffffff8a8e40a0 RDI: ffffffff8adefae0
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed10171e54b1
R10: ffffed10171e54b1 R11: 1ffff110171e54b0 R12: 7fffffffffffffff
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff8880b8f2a6e8
FS:  00007f66eee3b6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 0000000063b1b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 tick_program_event+0x34/0x120 kernel/time/tick-oneshot.c:25
 hrtimer_interrupt+0x59d/0x9c0 kernel/time/hrtimer.c:1891
 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: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 08 42 f7 48 89 df e8 e6 cd 42 f7 e8 71 c1 65 f7 fb bf 01 00 00 00 <e8> 46 4b 36 f7 65 8b 05 67 04 e1 75 85 c0 74 02 5b c3 e8 b4 15 df
RSP: 0018:ffffc90003b87bb8 EFLAGS: 00000286
RAX: 1bb87898497ffe00 RBX: ffff88802e8a9280 RCX: 1bb87898497ffe00
RDX: dffffc0000000000 RSI: ffffffff8a8c0300 RDI: 0000000000000001
RBP: ffff88802e8a9718 R08: dffffc0000000000 R09: ffffed1005d15251
R10: ffffed1005d15251 R11: 1ffff11005d15250 R12: 1ffff11005d152e3
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+0xb0/0x1230 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 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:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f66edf8ebe7
Code: ff ff 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
RSP: 002b:00007f66eee3b038 EFLAGS: 00000246
RAX: 0000000000000113 RBX: 00007f66ee1c5fa0 RCX: 00007f66edf8ebe9
RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007f66ee011e19 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f66ee1c6038 R14: 00007f66ee1c5fa0 R15: 00007ffda0dcae28
 </TASK>
CPU: 0 PID: 7847 Comm: syz.7.873 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:xrstor_from_user_sigframe arch/x86/kernel/fpu/xstate.h:304 [inline]
RIP: 0010:__restore_fpregs_from_user arch/x86/kernel/fpu/signal.c:259 [inline]
RIP: 0010:restore_fpregs_from_user arch/x86/kernel/fpu/signal.c:289 [inline]
RIP: 0010:__fpu_restore_sig arch/x86/kernel/fpu/signal.c:359 [inline]
RIP: 0010:fpu__restore_sig+0x5f3/0x1190 arch/x86/kernel/fpu/signal.c:493
Code: a1 00 49 8b 7d 00 4c 8b 6c 24 28 4c 89 ee ba 01 00 00 00 e8 2f 33 00 00 0f 01 cb 4c 89 f7 44 89 e8 48 8b 54 24 48 48 0f ae 2f <31> c0 41 89 c5 0f 01 ca 48 23 5c 24 58 31 ff 44 89 ee e8 e6 82 51
RSP: 0018:ffffc90003ba7b40 EFLAGS: 00040282
RAX: 0000000000000007 RBX: 0000000000000007 RCX: 0000000000080000
RDX: 0000000000000000 RSI: 000000000007ffff RDI: 00007f82955f5d00
RBP: ffffc90003ba7cf0 R08: 0000000000000000 R09: fffff52000774f90
R10: fffff52000774f90 R11: 1ffff92000774f8a R12: 1ffff92000774f74
R13: 0000000000000007 R14: 00007f82955f5d00 R15: 1ffff11003875a5e
FS:  00007f82955f66c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000007e5cb000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 restore_sigcontext arch/x86/kernel/signal.c:140 [inline]
 __ia32_sys_rt_sigreturn+0x649/0x790 arch/x86/kernel/signal.c:675
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f829478ebe7
Code: ff ff 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
RSP: 002b:00007f82955f60e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f82949c5fa8 RCX: 00007f829478ebe9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f82949c5fa8
RBP: 00007f82949c5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f82949c6038 R14: 00007ffec4a27c40 R15: 00007ffec4a27d28
 </TASK>