rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=8174/1/0x4000000000000000 softirq=23421/23421 fqs=3
rcu: 	(detected by 1, t=10502 jiffies, g=17993, q=379 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7686 Comm: syz.5.500 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:hrtimer_try_to_cancel+0x7/0x420
Code: c4 fe ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 <41> 56 41 55 41 54 53 48 83 ec 30 48 89 fb 49 be 00 00 00 00 00 fc
RSP: 0018:ffffc90000007978 EFLAGS: 00000006
RAX: ffffffff81adb021 RBX: ffff88810ea36568 RCX: ffff888109b15640
RDX: 0000000000010000 RSI: 0000000000000004 RDI: ffff88810ea36568
RBP: 00000000ffffffff R08: ffff88804b027a83 R09: 1ffff11009604f50
R10: dffffc0000000000 R11: ffffed1009604f51 R12: ffff88810ea36610
R13: dffffc0000000000 R14: ffff88810ea36568 R15: ffffffffffff4fc5
FS:  00007f690e5a56c0(0000) GS:ffff8880b8611000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3a1c25 CR3: 0000000120f30000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 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:lock_acquire+0x175/0x360
Code: 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 74 01 fb 65 48 8b 05 3b 7b 03 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90002e47c78 EFLAGS: 00000206
RAX: dfbcb27dbac98200 RBX: 0000000000000000 RCX: dfbcb27dbac98200
RDX: 0000000000000000 RSI: ffffffff8dbaa5f1 RDI: ffffffff8be34500
RBP: ffffffff823d2272 R08: 0000000000000000 R09: ffffffff823d2272
R10: dffffc0000000000 R11: ffffed1005e4aaa3 R12: 0000000000000000
R13: ffff88810e9270d8 R14: 0000000000000001 R15: 0000000000000246
 _raw_spin_lock+0x2e/0x40
 alloc_fd+0x62/0x6c0
 do_sys_openat2+0xfc/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f690d78ec29
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:00007f690e5a5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f690d9d5fa0 RCX: 00007f690d78ec29
RDX: 0000000000000002 RSI: 0000200000000080 RDI: ffffffffffffffff
RBP: 00007f690d811e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f690d9d6038 R14: 00007f690d9d5fa0 R15: 00007ffc28763fd8
 </TASK>
rcu: rcu_preempt kthread starved for 10496 jiffies! g17993 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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  running task     stack:26632 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:
CPU: 1 UID: 0 PID: 36 Comm: kworker/u10:1 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
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:smp_call_function_many_cond+0xd46/0x12d0
Code: e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5f 0b 00 eb 38 f3 90 42 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e <e8> 45 5f 0b 00 eb e4 44 89 e1 80 e1 07 80 c1 03 38 c1 7c e2 4c 89
RSP: 0018:ffffc900006af660 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff11009608341 RCX: ffff888100ead640
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900006af7e0 R08: ffffffff8fa3b637 R09: 1ffffffff1f476c6
R10: dffffc0000000000 R11: fffffbfff1f476c7 R12: ffff88804b041a08
R13: dffffc0000000000 R14: ffff88813663b1c0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881a3c11000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c34ad27 CR3: 000000000df36000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80
 smp_text_poke_batch_finish+0x5f9/0x1130
 arch_jump_label_transform_apply+0x1c/0x30
 static_key_enable_cpuslocked+0x128/0x250
 static_key_enable+0x1a/0x20
 toggle_allocation_gate+0xad/0x240
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
