rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=0064/1/0x4000000000000000 softirq=30784/30784 fqs=0
rcu: 	(detected by 1, t=10502 jiffies, g=19677, q=341 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8225 Comm: syz.8.539 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:do_raw_spin_unlock+0x4/0x240
Code: c1 03 38 c1 0f 8c 6a ff ff ff e8 67 d0 85 00 e9 60 ff ff ff 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 <55> 41 57 41 56 41 55 41 54 53 48 89 fb 49 bc 00 00 00 00 00 fc ff
RSP: 0018:ffffc90000007878 EFLAGS: 00000086
RAX: c53c34bbe9f71300 RBX: 0000000000000802 RCX: c53c34bbe9f71300
RDX: 0000000000000001 RSI: ffffffff8dbaa5db RDI: ffff88804b027a80
RBP: ffffc90000007918 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f00 R12: dffffc0000000000
R13: ffff88804b027b00 R14: ffff88804b027a80 R15: 1ffff92000000f10
FS:  00007f21411d46c0(0000) GS:ffff8880b8611000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3b624f CR3: 0000000112508000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 _raw_spin_unlock_irqrestore+0x78/0x110
 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:unwind_next_frame+0x1334/0x2390
Code: 0f b6 04 08 84 c0 75 27 49 63 07 4c 01 f8 49 8d 4f 04 4c 39 e0 48 0f 46 e9 49 8d 47 fc 48 0f 47 d8 4d 0f 46 ef 48 39 dd 76 a2 <e9> 7b ef ff ff 44 89 f9 80 e1 07 80 c1 03 38 c1 7c cc 4c 89 ff 48
RSP: 0018:ffffc90006967838 EFLAGS: 00000202
RAX: ffffffff9011298c RBX: ffffffff90112990 RCX: ffffffff90112994
RDX: ffffffff90112990 RSI: ffffffff90ba0284 RDI: ffffffff8be34420
RBP: ffffffff90112994 R08: 0000000000000001 R09: ffffffff8172d195
R10: dffffc0000000000 R11: ffffffff81ac5140 R12: ffffffff8958b12c
R13: ffffffff90112990 R14: ffffc90006967908 R15: ffffffff90112990
 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
 security_inode_alloc+0x39/0x330
 inode_init_always_gfp+0x9ed/0xdc0
 alloc_inode+0x82/0x1b0
 __sock_create+0x12d/0x9f0
 __sys_socketpair+0x1c5/0x560
 __x64_sys_socketpair+0x9b/0xb0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f214038ec29
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:00007f21411d4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f21405d5fa0 RCX: 00007f214038ec29
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 000000000000001e
RBP: 00007f2140411e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000240 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f21405d6038 R14: 00007f21405d5fa0 R15: 00007ffd6eb13528
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g19677 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=16796
rcu: rcu_preempt kthread starved for 10502 jiffies! g19677 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:26920 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>
