rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=76569, q=257 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10500 (4295001812-4294991312), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10500 jiffies! g76569 f0x2 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:24816 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5409 [inline]
 __schedule+0x17e8/0x4a50 kernel/sched/core.c:6746
 __schedule_loop kernel/sched/core.c:6823 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6838
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2582
 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:2030
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2232
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </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: 20071 Comm: syz-executor.3 Not tainted 6.9.0-rc3-next-20240409-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline]
RIP: 0010:rcu_is_watching+0x10/0xb0 kernel/rcu/tree.c:725
Code: 08 0a 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 65 ff 05 c8 84 87 7e <e8> fb 6a 08 0a 89 c3 83 f8 08 73 7a 49 bf 00 00 00 00 00 fc ff df
RSP: 0018:ffffc90000a18a40 EFLAGS: 00000087
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff81727474
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fac31a8
RBP: ffffc90000a18bc0 R08: ffffffff8fac31af R09: 1ffffffff1f58635
R10: dffffc0000000000 R11: fffffbfff1f58636 R12: 1ffff92000143154
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffc90000a18c80
FS:  00007f2c64c0c6c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdd8a5025a4 CR3: 00000000242e4000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0xe3/0x550 kernel/locking/lockdep.c:5725
 rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 __lock_task_sighand+0x49/0x2d0 kernel/signal.c:1397
 lock_task_sighand include/linux/sched/signal.h:746 [inline]
 send_sigqueue+0x25d/0x760 kernel/signal.c:1997
 posix_timer_event kernel/time/posix-timers.c:298 [inline]
 posix_timer_fn+0x18a/0x3a0 kernel/time/posix-timers.c:324
 __run_hrtimer kernel/time/hrtimer.c:1692 [inline]
 __hrtimer_run_queues+0x5a5/0xd50 kernel/time/hrtimer.c:1756
 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
 __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 6a 2d e3 f5 48 89 df e8 82 6d e4 f5 e8 3d d5 0d f6 fb bf 01 00 00 00 <e8> 32 56 d6 f5 65 8b 05 63 66 74 74 85 c0 74 06 5b c3 cc cc cc cc
RSP: 0018:ffffc900041afc70 EFLAGS: 00000282
RAX: 09476c5ae2940600 RBX: ffff888029725340 RCX: ffffffff94772703
RDX: dffffc0000000000 RSI: ffffffff8bcad7c0 RDI: 0000000000000001
RBP: ffffc900041afdb0 R08: ffffffff8fac31af R09: 1ffffffff1f58635
R10: dffffc0000000000 R11: fffffbfff1f58636 R12: 0000000000000021
R13: 1ffff110052e4afb R14: ffff8880297257d8 R15: ffff888029725340
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x14dd/0x1740 kernel/signal.c:2914
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
 do_syscall_64+0x10a/0x240 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x72/0x7a
RIP: 0033:0x7f2c63e7de67
Code: 14 25 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89
RSP: 002b:00007f2c64c0c178 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f2c63fabf88 RCX: 00007f2c63e7de69
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2c63fabf88
RBP: 00007f2c63fabf80 R08: 00007f2c64c0c6c0 R09: 00007f2c64c0c6c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2c63fabf8c
R13: 000000000000000b R14: 00007ffc685243e0 R15: 00007ffc685244c8
 </TASK>