rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=19197, q=292 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294966484-4294955982), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g19197 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=9282
rcu: rcu_preempt kthread starved for 10502 jiffies! g19197 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 ->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 stack:26728 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>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8060 Comm: syz.3.606 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_release+0x296/0x3e0
Code: 24 08 48 c7 c7 63 98 ba 8d e8 a6 ef dc 09 b8 ff ff ff ff 65 0f c1 05 49 8d 03 11 83 f8 01 75 51 48 c7 44 24 20 00 00 00 00 9c <8f> 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01
RSP: 0018:ffffc900001e0810 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000087 RCX: 6f76ee75560b2100
RDX: 0000000000000003 RSI: ffffffff8dba9863 RDI: ffffffff8be33e80
RBP: ffff888022d80b68 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200003c100 R12: 0000000000000003
R13: 0000000000000003 R14: ffff888136627a98 R15: ffff888022d80000
FS:  00007f741faf16c0(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f004bc31d58 CR3: 0000000028f20000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 _raw_spin_unlock_irqrestore+0x70/0x110
 hrtimer_try_to_cancel+0x3be/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:generic_write_checks_count+0x359/0x540
Code: 90 03 00 00 4c 03 75 00 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 f7 e8 1a f6 ee ff 49 8b 2e <48> c7 c7 ff ff ff ff 48 89 ee e8 c8 79 8b ff 48 83 fd ff 74 6a 48
RSP: 0018:ffffc900064cfbc8 EFLAGS: 00000246
RAX: 1ffff11003e8d312 RBX: 0000000000000000 RCX: dffffc0000000000
RDX: ffffc90027715000 RSI: 0000000000000037 RDI: 0000000000000038
RBP: 0000000008800000 R08: ffff8881110fa997 R09: 1ffff1102221f532
R10: dffffc0000000000 R11: ffffed102221f533 R12: 7fffffffffffffff
R13: ffff888022d80000 R14: ffff88801f469890 R15: ffff88810e075000
 generic_write_checks+0x61/0x110
 shmem_file_write_iter+0x8a/0x120
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f741eb8eba9
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:00007f741faf1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f741edd5fa0 RCX: 00007f741eb8eba9
RDX: 0000000000000040 RSI: 0000200000000180 RDI: 000000000000000a
RBP: 00007f741ec11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f741edd6038 R14: 00007f741edd5fa0 R15: 00007ffff3805468
 </TASK>
