rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=78c4/1/0x4000000000000000 softirq=554416/554416 fqs=1
rcu: 	(detected by 1, t=10502 jiffies, g=381345, q=345 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 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 24 c6 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 bf 32 0c 48 89 df 4c 89
RSP: 0018:ffffffff8e007b88 EFLAGS: 00000887
RAX: 0000000080000000 RBX: ffff8881b78679d0 RCX: dffffc0000000000
RDX: 0000000000000002 RSI: 0000000000000002 RDI: ffff8881b78679d0
RBP: 0000000080000000 R08: ffff8881b7867853 R09: 1ffff11036f0cf0a
R10: dffffc0000000000 R11: ffffed1036f0cf0b R12: dffffc0000000000
R13: 1ffffffff1b8c499 R14: 0000000080000000 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff88818e40f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff7ded7bff8 CR3: 0000000118491000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 __schedule+0x21ae/0x4fb0
 schedule_idle+0x51/0x90
 do_idle+0x499/0x500
 cpu_startup_entry+0x43/0x60
 rest_init+0x2de/0x300
 start_kernel+0x380/0x3d0
 x86_64_start_reservations+0x24/0x30
 x86_64_start_kernel+0x143/0x1c0
 common_startup_64+0x13e/0x147
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g381345 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:27504 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: 1 UID: 0 PID: 29110 Comm: kworker/u10:3 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:__sanitizer_cov_trace_pc+0x5c/0x70
Code: 48 16 00 00 83 fa 02 75 21 48 8b 91 50 16 00 00 48 8b 32 48 8d 7e 01 8b 89 4c 16 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 <e9> ff 3e b5 09 cc 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90
RSP: 0018:ffffc900070f7698 EFLAGS: 00000293
RAX: ffffffff81b6c32d RBX: 1ffff1102420856d RCX: ffff8881709624c0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900070f77e0 R08: ffffffff8fc25277 R09: 1ffffffff1f84a4e
R10: dffffc0000000000 R11: fffffbfff1f84a4f R12: ffff888121042b68
R13: dffffc0000000000 R14: ffff88823c63bb00 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8882a9a0f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff7dc1f6d58 CR3: 000000000e13a000 CR4: 0000000000352ef0
DR0: 0000000000050000 DR1: 0000000000054000 DR2: 000000000000c000
DR3: 0000000000003000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 smp_call_function_many_cond+0xcfd/0x1270
 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/0x250
 process_scheduled_works+0xaec/0x17a0
 worker_thread+0x89f/0xd90
 kthread+0x726/0x8b0
 ret_from_fork+0x51b/0xa40
 ret_from_fork_asm+0x1a/0x30
 </TASK>
