rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10501 ticks this GP) idle=d83c/1/0x4000000000000000 softirq=37704/37704 fqs=0
rcu: 	(t=10501 jiffies g=19933 q=1749 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10500 jiffies! g19933 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=7452
rcu: rcu_preempt kthread starved for 10502 jiffies! g19933 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:27248 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+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
CPU: 0 UID: 0 PID: 9658 Comm: syz.1.987 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:xfrm_alloc_spi+0x3b1/0xf30
Code: 94 c0 49 83 c5 d8 0f 94 c1 08 c1 74 0a e8 67 09 9e f7 e9 14 02 00 00 49 8d 9d c4 00 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 20 <84> c0 0f 85 9f 01 00 00 8b 1b 89 df 44 89 f6 e8 fb 0a 9e f7 44 39
RSP: 0018:ffffc900043370e0 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffff8880271b5bc4 RCX: 0000000000080000
RDX: ffffc90003769000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90004337230 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000866e0c R12: dffffc0000000000
R13: ffff8880271b5b00 R14: 0000000000000000 R15: ffffc900043376a0
FS:  00007f82f6d6d6c0(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000440 CR3: 0000000110dfe000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 xfrm_alloc_userspi+0x70b/0xc90
 xfrm_user_rcv_msg+0x7a3/0xab0
 netlink_rcv_skb+0x208/0x470
 xfrm_netlink_rcv+0x79/0x90
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x505/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __x64_sys_sendmsg+0x19b/0x260
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f82f5f8ebe9
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:00007f82f6d6d038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f82f61b5fa0 RCX: 00007f82f5f8ebe9
RDX: 0000000000000000 RSI: 0000200000000440 RDI: 0000000000000003
RBP: 00007f82f6011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f82f61b6038 R14: 00007f82f61b5fa0 R15: 00007ffd14b77098
 </TASK>
