rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=aeb/1/0x4000000000000000 softirq=52408/52409 fqs=2 
	(t=10500 jiffies g=70449 q=107)
rcu: rcu_preempt kthread starved for 10495 jiffies! g70449 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:27008 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 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: 16639 Comm: syz.9.3143 Not tainted 5.15.181-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:127 [inline]
RIP: 0010:check_preemption_disabled+0x59/0x110 lib/smp_processor_id.c:19
Code: 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 cc 65 4c 8b 3d 36 32 61 76 41 f6 47 2f 04
RSP: 0018:ffffc90002ea7940 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff88801faa5940 RCX: 0000000080000000
RDX: 0000000000000000 RSI: ffffffff8a0b2260 RDI: ffffffff8a59a2c0
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed1027fd4641
R10: ffffed1027fd4641 R11: 1ffff11027fd4640 R12: dffffc0000000000
R13: 0000000000000246 R14: ffffffff8c11bf20 R15: 00000000ffffffff
FS:  00007fa93c5656c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffe3511d58 CR3: 000000005b875000 CR4: 00000000003526e0
DR0: 0000000000000007 DR1: 0000000000000002 DR2: 0000000000000008
DR3: 0000000000000006 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lockdep_recursion_finish kernel/locking/lockdep.c:436 [inline]
 lock_is_held_type+0x100/0x190 kernel/locking/lockdep.c:5667
 lock_is_held include/linux/lockdep.h:287 [inline]
 ___might_sleep+0xf2/0x600 kernel/sched/core.c:9605
 __might_fault+0x6b/0x110 mm/memory.c:5354
 __copy_to_user include/linux/uaccess.h:143 [inline]
 save_xstate_epilog arch/x86/kernel/fpu/signal.c:104 [inline]
 copy_fpstate_to_sigframe+0x882/0xb90 arch/x86/kernel/fpu/signal.c:217
 get_sigframe arch/x86/kernel/signal.c:295 [inline]
 __setup_rt_frame arch/x86/kernel/signal.c:471 [inline]
 setup_rt_frame arch/x86/kernel/signal.c:780 [inline]
 handle_signal arch/x86/kernel/signal.c:824 [inline]
 arch_do_signal_or_restart+0x67a/0x1300 arch/x86/kernel/signal.c:869
 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+0xb1/0x140 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: 0033:0x7fa93e6fd969
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:00007fa93c5650e8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007fa93e924fa8 RCX: 00007fa93e6fd969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa93e924fa8
RBP: 00007fa93e924fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa93e924fac
R13: 0000000000000000 R14: 00007ffca6354110 R15: 00007ffca63541f8
 </TASK>
NMI backtrace for cpu 0
CPU: 0 PID: 16636 Comm: syz.1.3142 Not tainted 5.15.181-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
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:3932 [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:__syscall_enter_from_user_work kernel/entry/common.c:93 [inline]
RIP: 0010:syscall_enter_from_user_mode+0x2a/0x70 kernel/entry/common.c:114
Code: 41 56 53 48 89 f3 49 89 fe 48 8b 7c 24 10 e8 3d f6 ff ff eb 31 eb 35 e8 04 a6 dc f7 e8 ff a3 dc f7 fb 65 48 8b 05 76 37 61 76 <48> 8b 70 08 40 f6 c6 3f 74 0b 4c 89 f7 5b 41 5e e9 51 db c4 f7 48
RSP: 0018:ffffc90002d9ff08 EFLAGS: 00000286
RAX: ffff88802b6f0000 RBX: 000000000000000f RCX: 27560d20f2c22600
RDX: dffffc0000000000 RSI: ffffffff8a0b0fc0 RDI: ffffffff8a59a2c0
RBP: ffffc90002d9ff48 R08: dffffc0000000000 R09: fffffbfff1ad155e
R10: fffffbfff1ad155e R11: 1ffffffff1ad155d R12: 0000000000000000
R13: 0000000000000000 R14: ffffc90002d9ff58 R15: 0000000000000000
 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe79e224b39
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007fe79c0efa80 EFLAGS: 00000202 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007fe79e4affa0 RCX: 00007fe79e224b39
RDX: 00007fe79c0efa80 RSI: 00007fe79c0efbb0 RDI: 0000000000000021
RBP: 00007fe79e30aab1 R08: 0000000008000f28 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe79e4affa0 R15: 00007ffc94ac1c28
 </TASK>