rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=542c/1/0x4000000000000000 softirq=55536/55536 fqs=0
rcu: 	(detected by 0, t=10505 jiffies, g=47625, q=409 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 12209 Comm: syz.3.1720 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:lock_acquire+0x154/0x360
Code: 8d e8 20 02 dd 09 b8 ff ff ff ff 65 0f c1 05 c3 9f 03 11 83 f8 01 0f 85 c9 00 00 00 48 c7 44 24 30 00 00 00 00 9c 8f 44 24 30 <f7> 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00
RSP: 0018:ffffc900001e07e0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 8e41455f9d6d2a00
RDX: 0000000000000000 RSI: ffffffff8dba9832 RDI: ffffffff8be33e00
RBP: ffffffff81ada78b R08: 0000000000000000 R09: ffffffff81ada78b
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: 0000000000000000
R13: ffff888136627a98 R14: 0000000000000001 R15: 0000000000000046
FS:  00007f5adedf66c0(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b34420ff8 CR3: 0000000115bc4000 CR4: 00000000000006f0
DR0: 00002000000005c0 DR1: 00002000000005c0 DR2: 00002000000005c0
DR3: 00002000000005c0 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 _raw_spin_lock_irqsave+0xa7/0xf0
 hrtimer_try_to_cancel+0x22b/0x420
 hrtimer_cancel+0x3b/0x50
 cpu_clock_event_stop+0xd9/0x130
 __perf_event_overflow+0x580/0xe40
 perf_swevent_hrtimer+0x3c5/0x550
 __hrtimer_run_queues+0x4e0/0xc60
 hrtimer_interrupt+0x45b/0xaa0
 __sysvec_apic_timer_interrupt+0x10b/0x410
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:rcu_is_watching+0x5a/0xb0
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 bc cc 7c 00 48 c7 c3 98 ff a1 92 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 34 8b 03 65 ff 0d d9 5d fa 10 74 11 83 e0 04 c1 e8 02 5b
RSP: 0018:ffffc90003cf7410 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffff888136632f98 RCX: 8e41455f9d6d2a00
RDX: ffffc90003cf7501 RSI: ffffffff8be33de0 RDI: ffffffff8be33da0
RBP: dffffc0000000000 R08: ffffc90003cf7948 R09: 0000000000000000
R10: ffffc90003cf75b8 R11: fffff5200079eeb9 R12: ffffc90003cf7958
R13: ffffffff8172d195 R14: ffffffff8dbe2d18 R15: dffffc0000000000
 lock_release+0x4b/0x3e0
 unwind_next_frame+0x19a9/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 alloc_empty_file+0x55/0x1d0
 path_openat+0x107/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ae0b8eba9
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:00007f5adedf6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f5ae0dd5fa0 RCX: 00007f5ae0b8eba9
RDX: 0000000000008202 RSI: 0000200000000200 RDI: ffffffffffffff9c
RBP: 00007f5ae0c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5ae0dd6038 R14: 00007f5ae0dd5fa0 R15: 00007ffe01d30238
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g47625 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=21651
rcu: rcu_preempt kthread starved for 10505 jiffies! g47625 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26664 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 rcu_gp_fqs_loop+0x301/0x1540
 rcu_gp_kthread+0x99/0x390
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
