rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=1fe4/1/0x4000000000000000 softirq=138605/138626 fqs=1
rcu: 	(detected by 0, t=10505 jiffies, g=118609, q=23 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 29870 Comm: syz.2.6486 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:mm_get_cid+0xab/0x130
Code: 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 49 c7 c5 c8 d4 d7 8d 49 c1 ed 03 bd 00 00 00 80 eb 07 44 89 f0 f7 d8 71 d4 f3 90 <43> 0f b6 44 25 00 84 c0 75 41 44 8b 3d 6c 5d 44 0c 48 89 df 4c 89
RSP: 0018:ffffc900088ef7a8 EFLAGS: 00000887
RAX: 0000000080000000 RBX: ffff8881749f17d0 RCX: dffffc0000000000
RDX: 0000000000000002 RSI: 0000000000000002 RDI: ffff8881749f17d0
RBP: 0000000080000000 R08: ffff8881749f1653 R09: 1ffff1102e93e2ca
R10: dffffc0000000000 R11: ffffed102e93e2cb R12: dffffc0000000000
R13: 1ffffffff1bafa99 R14: 0000000080000000 R15: 0000000000000002
FS:  00007f0b3ffae6c0(0000) GS:ffff8882a9926000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f75cd604ff8 CR3: 0000000170f12000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __schedule+0x21b0/0x4fb0
 schedule+0x164/0x360
 __futex_wait+0x1ee/0x420
 futex_wait+0x119/0x380
 do_futex+0x333/0x420
 __se_sys_futex+0x3a8/0x450
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0b3f19acb9
Code: Unable to access opcode bytes at 0x7f0b3f19ac8f.
RSP: 002b:00007f0b3ffae0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f0b3f415fa8 RCX: 00007f0b3f19acb9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f0b3f415fa8
RBP: 00007f0b3f415fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b3f416038 R14: 00007ffd962aaa80 R15: 00007ffd962aab68
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g118609 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:27648 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 __schedule+0x14ef/0x4fb0
 schedule+0x164/0x360
 schedule_timeout+0x158/0x2c0
 rcu_gp_fqs_loop+0x312/0x1560
 rcu_gp_kthread+0x9d/0x3b0
 kthread+0x726/0x8b0
 ret_from_fork+0x51b/0xa40
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 2263 Comm: kworker/u9:3 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+0xce5/0x1270
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 94 b4 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 3f b0 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 23 b0
RSP: 0018:ffffc90008a3f6a0 EFLAGS: 00000293
RAX: ffffffff81b6e93d RBX: 1ffff110478c8129 RCX: ffff88810a558000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90008a3f7e0 R08: ffffffff8fceef77 R09: 1ffffffff1f9ddee
R10: dffffc0000000000 R11: fffffbfff1f9ddef R12: ffff88823c640948
R13: dffffc0000000000 R14: ffff88812103bb00 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff88818e326000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c26c1e1 CR3: 000000000e146000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80
 smp_text_poke_batch_finish+0x5f5/0x1160
 arch_jump_label_transform_apply+0x1c/0x30
 static_key_enable_cpuslocked+0x128/0x240
 static_key_enable+0x1a/0x20
 toggle_allocation_gate+0xab/0x290
 process_scheduled_works+0xaec/0x17a0
 worker_thread+0x89f/0xd90
 kthread+0x726/0x8b0
 ret_from_fork+0x51b/0xa40
 ret_from_fork_asm+0x1a/0x30
 </TASK>
