rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=f3e/1/0x4000000000000000 softirq=7597/7598 fqs=11 
	(t=10501 jiffies g=5877 q=830)
rcu: rcu_preempt kthread starved for 10480 jiffies! g5877 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:28744 pid:   13 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:4322 [inline]
 __schedule+0xf86/0x2180 kernel/sched/core.c:5073
 schedule+0xdb/0x280 kernel/sched/core.c:5152
 schedule_timeout+0x133/0x220 kernel/time/timer.c:1892
 rcu_gp_fqs_loop kernel/rcu/tree.c:2005 [inline]
 rcu_gp_kthread+0xcf6/0x2200 kernel/rcu/tree.c:2178
 kthread+0x37d/0x460 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
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: 6921 Comm: syz-executor.1 Not tainted 5.12.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:task_irq_context kernel/locking/lockdep.c:4407 [inline]
RIP: 0010:__lock_acquire+0x310/0x53d0 kernel/locking/lockdep.c:4838
Code: 03 80 3c 02 00 0f 85 81 37 00 00 48 8b 85 48 ff ff ff 48 8d b3 7c 09 00 00 45 31 f6 48 89 f2 48 89 b5 30 ff ff ff 49 89 47 18 <65> 8b 05 a1 94 ab 7e 85 c0 48 b8 00 00 00 00 00 fc ff df 41 0f 95
RSP: 0000:ffffc90003ed7930 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888101192340 RCX: 0000000000000001
RDX: ffff888101192cbc RSI: ffff888101192cbc RDI: ffff888101192ce8
RBP: ffffc90003ed7a48 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffff888101192b40 R12: 0000000000000109
R13: 0000000000000000 R14: 0000000000000000 R15: ffff888101192cd8
FS:  00007f052481b700(0000) GS:ffff8881f6700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002498f890 CR3: 000000011cb13006 CR4: 00000000001706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_acquire kernel/locking/lockdep.c:5510 [inline]
 lock_acquire+0x22a/0x8c0 kernel/locking/lockdep.c:5475
 __might_fault mm/memory.c:5021 [inline]
 __might_fault+0xef/0x160 mm/memory.c:5006
 __copy_to_user include/linux/uaccess.h:143 [inline]
 save_xstate_epilog arch/x86/kernel/fpu/signal.c:95 [inline]
 copy_fpstate_to_sigframe+0x62d/0x830 arch/x86/kernel/fpu/signal.c:208
 get_sigframe.constprop.0.isra.0+0x413/0x8d0 arch/x86/kernel/signal.c:274
 __setup_rt_frame arch/x86/kernel/signal.c:450 [inline]
 setup_rt_frame arch/x86/kernel/signal.c:702 [inline]
 handle_signal arch/x86/kernel/signal.c:746 [inline]
 arch_do_signal_or_restart+0xe1a/0x2620 arch/x86/kernel/signal.c:791
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x1db/0x250 kernel/entry/common.c:208
 irqentry_exit_to_user_mode+0x9/0x30 kernel/entry/common.c:314
 irqentry_exit+0x6c/0xb0 kernel/entry/common.c:405
 exc_page_fault+0x90/0xe0 arch/x86/mm/fault.c:1534
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:577
RIP: 0033:0x40a497
Code: c7 44 24 18 00 00 00 00 8b 7c 24 20 31 d2 be 01 4c 00 00 31 c0 e8 59 7b 05 00 e9 3b fe ff ff 48 6b 44 24 10 18 48 03 44 24 28 <48> 8b 48 10 48 8b 50 08 48 8b 30 8b 7c 24 1c e8 25 b3 00 00 89 44
RSP: 002b:00007f052481afc0 EFLAGS: 00010202
RAX: 000000002498f880 RBX: 000000000052bf00 RCX: 0000000000415827
RDX: 3489d4556223a246 RSI: 0000000000000000 RDI: 00007f052481b5f0
RBP: 0000000000000007 R08: 00007f052481afc0 R09: 0000000000000007
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffff
R13: 00000000004fd358 R14: 00000000004b69b5 R15: 00007f052481b6bc
NMI backtrace for cpu 0
CPU: 0 PID: 6914 Comm: syz-executor.3 Not tainted 5.12.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x114/0x14e lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x30/0x9c lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x120/0x170 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:39
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x1cc/0x252 kernel/rcu/tree_stall.h:341
 print_cpu_stall kernel/rcu/tree_stall.h:622 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:697 [inline]
 rcu_pending kernel/rcu/tree.c:3830 [inline]
 rcu_sched_clock_irq.cold+0x67c/0x11b6 kernel/rcu/tree.c:2650
 update_process_times+0x139/0x1b0 kernel/time/timer.c:1796
 tick_sched_handle+0x77/0x140 kernel/time/tick-sched.c:226
 tick_sched_timer+0x142/0x230 kernel/time/tick-sched.c:1369
 __run_hrtimer kernel/time/hrtimer.c:1537 [inline]
 __hrtimer_run_queues+0x1b7/0xc30 kernel/time/hrtimer.c:1601
 hrtimer_interrupt+0x2f3/0x950 kernel/time/hrtimer.c:1663
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline]
 __sysvec_apic_timer_interrupt+0x143/0x530 arch/x86/kernel/apic/apic.c:1106
 sysvec_apic_timer_interrupt+0x98/0xc0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x4f/0x90 kernel/locking/spinlock.c:199
Code: c0 40 b9 75 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 35 48 83 3d 6a ae d2 01 00 74 22 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 d7 4e a8 f9 65 8b 05 90 f3 5e 78 85 c0 74 08 4c
RSP: 0000:ffffc90003e77c80 EFLAGS: 00000282
RAX: 1ffffffff12eb728 RBX: dffffc0000000000 RCX: 1ffffffff14fdd61
RDX: dffffc0000000000 RSI: ffffffff880b2320 RDI: ffffffff8850c620
RBP: ffffc90003e77c88 R08: 0000000000000001 R09: 0000000000000001
R10: ffffed1021612978 R11: ffff88811bee8980 R12: ffff88810b094bc0
R13: 000000000000000b R14: ffff88810b094bc0 R15: ffff88810b094d01
 spin_unlock_irq include/linux/spinlock.h:404 [inline]
 get_signal+0x14d5/0x1c70 kernel/signal.c:2784
 arch_do_signal_or_restart+0x2b3/0x2620 arch/x86/kernel/signal.c:789
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x1db/0x250 kernel/entry/common.c:208
 irqentry_exit_to_user_mode+0x9/0x30 kernel/entry/common.c:314
 irqentry_exit+0x6c/0xb0 kernel/entry/common.c:405
 exc_page_fault+0x90/0xe0 arch/x86/mm/fault.c:1534
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:577
RIP: 0033:0x40a497
Code: c7 44 24 18 00 00 00 00 8b 7c 24 20 31 d2 be 01 4c 00 00 31 c0 e8 59 7b 05 00 e9 3b fe ff ff 48 6b 44 24 10 18 48 03 44 24 28 <48> 8b 48 10 48 8b 50 08 48 8b 30 8b 7c 24 1c e8 25 b3 00 00 89 44
RSP: 002b:00007f96ea75dfc0 EFLAGS: 00010206
RAX: 000000002496b628 RBX: 000000000052bf00 RCX: 0000000000415827
RDX: c4a808f62c5fa5ba RSI: 0000000000000000 RDI: 00007f96ea75e5f0
RBP: 0000000000000007 R08: 00007f96ea75dfc0 R09: 0000000000000007
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffff
R13: 00000000004fd358 R14: 00000000004b69b5 R15: 00007f96ea75e6bc
sched: RT throttling activated