syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6880
rcu: 	(detected by 0, t=10502 jiffies, g=16217, q=2735 ncpus=2)
task:syz.0.301       state:R  running task     stack:26952 pid:6880  tgid:6880  ppid:5958   task_flags:0x400040 flags:0x00004006
Call Trace:
 <IRQ>
 sched_show_task+0x49d/0x630 kernel/sched/core.c:7933
 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline]
 print_other_cpu_stall+0xf78/0x1340 kernel/rcu/tree_stall.h:681
 check_cpu_stall kernel/rcu/tree_stall.h:857 [inline]
 rcu_pending kernel/rcu/tree.c:3671 [inline]
 rcu_sched_clock_irq+0xa47/0x11b0 kernel/rcu/tree.c:2706
 update_process_times+0x235/0x2d0 kernel/time/timer.c:2473
 tick_sched_handle kernel/time/tick-sched.c:276 [inline]
 tick_nohz_handler+0x39a/0x520 kernel/time/tick-sched.c:297
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x503/0xd40 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45d/0xa90 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 8b d3 cb f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> b3 8b 95 f6 65 8b 05 dc dc fb 06 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc90003aafb40 EFLAGS: 00000206
RAX: c013c10a5e9bae00 RBX: 0000000000000a02 RCX: c013c10a5e9bae00
RDX: 0000000000000006 RSI: ffffffff8d03a0c9 RDI: 0000000000000001
RBP: ffffc90003aafbd0 R08: ffffffff8f1d5a37 R09: 1ffffffff1e3ab46
R10: dffffc0000000000 R11: fffffbfff1e3ab47 R12: dffffc0000000000
R13: ffffffff8e16a380 R14: ffffffff8e16a380 R15: 1ffff92000755f68
 unlock_rt_mutex_safe kernel/locking/rtmutex.c:344 [inline]
 rt_mutex_slowunlock+0x493/0x8a0 kernel/locking/rtmutex.c:1454
 spin_unlock_irqrestore include/linux/spinlock_rt.h:122 [inline]
 vga_put drivers/pci/vgaarb.c:553 [inline]
 vga_arb_release+0x3fb/0xa90 drivers/pci/vgaarb.c:1455
 __fput+0x45b/0xa80 fs/file_table.c:468
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f40e894ebe9
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:00007ffdfc93c728 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000002310c RCX: 00007f40e894ebe9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f40e8b87da0 R08: 0000000000000001 R09: 00000004fc93ca1f
R10: 0000001b30520000 R11: 0000000000000246 R12: 00007f40e8b8609c
R13: 00007f40e8b86090 R14: ffffffffffffffff R15: 00007ffdfc93c840
 </TASK>