rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10528 ticks this GP) idle=dd1/1/0x4000000000000000 softirq=29248/29250 fqs=379 
	(t=10502 jiffies g=40149 q=246)
rcu: rcu_preempt kthread starved for 9745 jiffies! g40149 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:26872 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 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 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:108 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562
NMI backtrace for cpu 1
CPU: 1 PID: 8852 Comm: syz.0.909 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x223/0x390 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x320/0x600 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0x8d9/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 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:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x30/0x80 kernel/kcov.c:293
Code: 8b 15 c4 e6 81 7e 65 8b 05 c5 e6 81 7e 25 00 01 ff 00 74 10 3d 00 01 00 00 75 5b 83 ba 34 16 00 00 00 74 52 8b 82 10 16 00 00 <83> f8 03 75 47 48 8b 8a 18 16 00 00 44 8b 92 14 16 00 00 49 c1 e2
RSP: 0018:ffffc9000405fa98 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88806403b700 RCX: 0000000000000000
RDX: ffff888064039dc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000405fc50 R08: ffffffff812f445d R09: fffff5200080bfb0
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: 00007fffc1e3b900 R14: 0000000000000344 R15: dffffc0000000000
 fpu__restore_sig+0xfd/0x1100 arch/x86/kernel/fpu/signal.c:450
 restore_sigcontext+0x638/0x710 arch/x86/kernel/signal.c:139
 __do_sys_rt_sigreturn+0x190/0x250 arch/x86/kernel/signal.c:674
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f117eff65a6
Code: 77 f8 48 89 f8 48 89 eb eb 12 66 2e 0f 1f 84 00 00 00 00 00 48 8b 4b 08 48 83 c3 08 48 39 d1 72 f3 48 83 e8 08 48 39 f2 73 17 <66> 2e 0f 1f 84 00 00 00 00 00 48 8b 70 f8 48 83 e8 08 48 39 f2 72
RSP: 002b:00007fffc1e3bce0 EFLAGS: 00000287
RAX: 00007f117e81f4b8 RBX: 00007f117e81bc18 RCX: ffffffff81f0a44a
RDX: ffffffff81f0a44a RSI: ffffffff81f0ab68 RDI: 00007f117e820818
RBP: 00007f117e815940 R08: 00007f117e81b0a8 R09: 00007f117f322000
R10: 00007f117e78f008 R11: 0000000000000009 R12: 00007f117e815938
R13: 000000000000001b R14: 00007fffc1e3be68 R15: 00007f117e78f008
 </TASK>