syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 1, t=15605 jiffies, g=262821, q=17998)
rcu: All QSes seen, last rcu_preempt kthread activity 15605 (4295100946-4295085341), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor.1  R  running task    26168 15610   7212 0x20020008
Call Trace:
 <IRQ>
 sched_show_task kernel/sched/core.c:5961 [inline]
 sched_show_task.cold+0x2e2/0x343 kernel/sched/core.c:5936
 print_other_cpu_stall kernel/rcu/tree_stall.h:430 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:558 [inline]
 rcu_pending kernel/rcu/tree.c:3225 [inline]
 rcu_sched_clock_irq.cold+0xb9b/0xcfa kernel/rcu/tree.c:2296
 update_process_times+0x25/0x60 kernel/time/timer.c:1727
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176
 tick_sched_timer+0x4e/0x140 kernel/time/tick-sched.c:1320
 __run_hrtimer kernel/time/hrtimer.c:1520 [inline]
 __hrtimer_run_queues+0x5ca/0xed0 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1113 [inline]
 smp_apic_timer_interrupt+0x15b/0x600 arch/x86/kernel/apic/apic.c:1138
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:preempt_schedule_irq+0xa6/0x150 kernel/sched/core.c:4346
Code: 00 00 e8 9d fc 7f f9 e8 88 97 a9 f9 4c 89 e8 48 c1 e8 03 80 3c 18 00 75 7a 48 83 3d 23 a6 c5 01 00 74 6c fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 60 d1 ff ff 48 c7 c0 28 c2 94 89 48 c1 e8 03 80
RSP: 0018:ffffc90004bff8d0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff1329846 RBX: dffffc0000000000 RCX: 1ffffffff186a0ec
RDX: 0000000000000000 RSI: ffff88805376ecb0 RDI: ffff88805376ec84
RBP: ffffed100a6edc78 R08: 0000000000000001 R09: fffffbfff185cd61
R10: ffffffff8c2e6b07 R11: fffffbfff185cd60 R12: ffff88805376e3c0
R13: ffffffff8994c230 R14: 0000000000000000 R15: 0000000000000000
 retint_kernel+0x1b/0x2b
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline]
RIP: 0010:lock_acquire+0x267/0x8f0 kernel/locking/lockdep.c:4937
Code: 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 c6 05 00 00 48 83 3d d5 3b 3b 08 00 0f 84 65 04 00 00 48 8b 3c 24 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 08 48 c7
RSP: 0018:ffffc90004bff9a0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff02
RAX: 1ffffffff1329844 RBX: ffff88805376e3c0 RCX: ffffffff81592eeb
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000282
RBP: 0000000000000000 R08: 0000000000000001 R09: fffffbfff185cd61
R10: ffffffff8c2e6b07 R11: fffffbfff185cd60 R12: 0000000000000002
R13: ffffc90005002fc8 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:208 [inline]
 srcu_read_lock include/linux/srcu.h:155 [inline]
 vcpu_enter_guest+0x21d2/0x59d0 arch/x86/kvm/x86.c:8379
 vcpu_run arch/x86/kvm/x86.c:8544 [inline]
 kvm_arch_vcpu_ioctl_run+0x3fb/0x16e0 arch/x86/kvm/x86.c:8766
 kvm_vcpu_ioctl+0x493/0xe60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3138
 kvm_vcpu_compat_ioctl+0x1ab/0x350 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3334
 __do_compat_sys_ioctl fs/ioctl.c:857 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:808 [inline]
 __ia32_compat_sys_ioctl+0x23d/0x2b0 fs/ioctl.c:808
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x270/0xe90 arch/x86/entry/common.c:396
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
rcu: rcu_preempt kthread starved for 15605 jiffies! g262821 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    28848    10      2 0x80004000
Call Trace:
 schedule+0xd0/0x2a0 kernel/sched/core.c:4163
 schedule_timeout+0x35c/0x850 kernel/time/timer.c:1898
 rcu_gp_fqs_loop kernel/rcu/tree.c:1674 [inline]
 rcu_gp_kthread+0x9bf/0x1960 kernel/rcu/tree.c:1836
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352