rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10499 ticks this GP) idle=ecd/1/0x4000000000000000 softirq=9257/9257 fqs=0 
	(t=10500 jiffies g=9945 q=13818)
rcu: rcu_preempt kthread starved for 10500 jiffies! g9945 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:27656 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 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
 </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: 4835 Comm: syz.4.163 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:check_preemption_disabled+0x4b/0x110 lib/smp_processor_id.c:55
Code: 0d b2 71 59 76 f7 c1 ff ff ff 7f 74 1f 65 48 8b 0c 25 28 00 00 00 48 3b 4c 24 08 0f 85 c4 00 00 00 48 83 c4 10 5b 41 5e 41 5f <5d> c3 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 74
RSP: 0018:ffffc9000349feb8 EFLAGS: 00000086
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0ee5e06ebeec4000
RDX: 0000000000000002 RSI: ffffffff8a59a220 RDI: ffffffff8a59a1e0
RBP: ffffc9000349ff48 R08: dffffc0000000000 R09: fffffbfff1ad31be
R10: fffffbfff1ad31be R11: 1ffffffff1ad31bd R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 000000000000000f
FS:  00007f5f75fca6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f77f99fa8 CR3: 0000000060b30000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline]
 rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:1123
 trace_irq_enable include/trace/events/preemptirq.h:40 [inline]
 trace_hardirqs_on_prepare+0xb9/0x1f0 kernel/trace/trace_preemptirq.c:32
 __exit_to_user_mode kernel/entry/common.c:132 [inline]
 syscall_exit_to_user_mode+0x1b/0x40 kernel/entry/common.c:309
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5f77c219b0
Code: 44 24 20 0f 29 44 24 30 0f 29 44 24 40 48 8b 44 24 08 ff d0 48 83 c4 50 31 c0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 80 00 00 00 00 <c3> 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 c3 66 66 2e 0f 1f
RSP: 002b:00007f5f75fc9b38 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f5f77f99fa8 RCX: 00007f5f77d62be9
RDX: 00007f5f75fc9b40 RSI: 00007f5f75fc9c70 RDI: 0000000000000011
RBP: 00007f5f77f99fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5f77f9a038 R14: 00007ffd08a1e7c0 R15: 00007ffd08a1e8a8
 </TASK>
NMI backtrace for cpu 0
CPU: 0 PID: 4844 Comm: syz.4.163 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <IRQ>
 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_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+0x6d8/0x1110 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:1690 [inline]
 __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
 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_rq_unlock_irq+0x13/0x90 kernel/sched/sched.h:1339
Code: c0 48 8b 3c 24 e8 1d bc 68 00 eb b5 66 2e 0f 1f 84 00 00 00 00 00 90 41 57 41 56 53 eb 11 e8 e4 e5 5e 08 e8 0f 74 2a 00 fb 5b <41> 5e 41 5f c3 49 be 00 00 00 00 00 fc ff df 49 89 ff 48 8d 9f 58
RSP: 0018:ffffc9000341f848 EFLAGS: 00000286
RAX: 87ecc8587c862100 RBX: ffff8880b903a300 RCX: 87ecc8587c862100
RDX: dffffc0000000000 RSI: ffffffff8a0b1620 RDI: ffffffff8a59a240
RBP: ffffc9000341fa40 R08: dffffc0000000000 R09: ffffed1017207461
R10: ffffed1017207461 R11: 1ffff11017207460 R12: 1ffff110172075a3
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff8880b903b048
 __schedule+0x1464/0x4390 kernel/sched/core.c:6401
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 freezable_schedule include/linux/freezer.h:172 [inline]
 futex_wait_queue_me+0x22d/0x440 kernel/futex/core.c:2863
 futex_wait+0x202/0x5c0 kernel/futex/core.c:2964
 do_futex+0xd1c/0x1240 kernel/futex/core.c:3982
 __do_sys_futex kernel/futex/core.c:4059 [inline]
 __se_sys_futex+0x3a3/0x430 kernel/futex/core.c:4040
 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: 0033:0x7f5f77d62be9
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:00007f5f75fa90e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f5f77f9a098 RCX: 00007f5f77d62be9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5f77f9a098
RBP: 00007f5f77f9a090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5f77f9a128 R14: 00007ffd08a1e7c0 R15: 00007ffd08a1e8a8
 </TASK>