rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=8434/1/0x4000000000000000 softirq=22399/22400 fqs=1
rcu: 	(detected by 0, t=10505 jiffies, g=18257, q=396 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8491 Comm: syz.2.914 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 6e e0 09 b8 ff ff ff ff 65 0f c1 05 23 12 24 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: 35c3c8d697438c00
RDX: 0000000000000000 RSI: ffffffff8dd8c8ae RDI: ffffffff8c03d4e0
RBP: ffffffff81ae2efb R08: 0000000000000000 R09: ffffffff81ae2efb
R10: dffffc0000000000 R11: ffffed1026cc4f59 R12: 0000000000000000
R13: ffff888136627ad8 R14: 0000000000000001 R15: 0000000000000046
FS:  00007f218379b6c0(0000) GS:ffff8881a3a03000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32418ff8 CR3: 000000011c33e000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 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+0x3b8/0x500
 __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:alloc_fd+0x1a5/0x6c0
Code: e6 ff 48 89 6c 24 10 c1 ed 06 44 8d 2c ed 00 00 00 00 4d 03 2e 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 4c 89 ef e8 d1 b0 e6 ff 48 8b 4c 24 10 83 e1 3f 48 c7 c3 ff
RSP: 0018:ffffc90002fdfdb0 EFLAGS: 00000246
RAX: 1ffff1100908d3d0 RBX: 0000000000000001 RCX: dffffc0000000000
RDX: ffff888108eeba00 RSI: 0000000000000100 RDI: 000000000000000c
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520005fbfa4 R12: 1ffff1100721ec73
R13: ffff888048469e80 R14: ffff8880390f6398 R15: 0000000000000100
 __sys_socketpair+0x67/0x560
 __x64_sys_socketpair+0x9b/0xb0
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f218298ec29
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:00007f218379b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f2182bd5fa0 RCX: 00007f218298ec29
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000001
RBP: 00007f2182a11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 00002000000029c0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2182bd6038 R14: 00007f2182bd5fa0 R15: 00007ffc67b85ad8
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g18257 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27224 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
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+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 4607 Comm: kworker/u9:5 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+0xd33/0x12d0
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 26 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 d1 6e 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 b5 6e
RSP: 0018:ffffc900049ff640 EFLAGS: 00000293
RAX: ffffffff81b4e79b RBX: 1ffff11026cc7ffd RCX: ffff888025af9d00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900049ff7c0 R08: ffffffff8fc34277 R09: 1ffffffff1f8684e
R10: dffffc0000000000 R11: fffffbfff1f8684f R12: ffff88813663ffe8
R13: dffffc0000000000 R14: ffff88804b03b200 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b8403000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b324f9ff8 CR3: 000000000e138000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
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+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
