syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5602/2:b..l
	(detected by 0, t=10502 jiffies, g=16841, q=609)
task:syz.3.259       state:R  running task     stack:24096 pid: 5602 ppid:  4883 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:pfkey_send_acquire+0x1711/0x2d70 net/key/af_key.c:-1
Code: 85 30 08 00 00 41 be 01 00 00 00 89 d9 41 d3 e6 48 8b 44 24 68 44 23 30 31 ff 44 89 f6 e8 f7 c5 cb f8 40 80 e5 01 40 0f b6 dd <31> ff 89 de e8 e6 c4 cb f8 84 db 0f 84 8d 07 00 00 45 85 f6 0f 84
RSP: 0018:ffffc9000335ee48 EFLAGS: 00000246
RAX: ffffffff88ac0979 RBX: 0000000000000000 RCX: ffff88801cefd940
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffff888060e97c75
R10: ffffed100c1d2f8f R11: 1ffff1100c1d2f8e R12: ffff88801abd3000
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8d32a050
 km_query+0xe3/0x1d0 net/xfrm/xfrm_state.c:2250
 xfrm_state_find+0x1f5c/0x2a80 net/xfrm/xfrm_state.c:1164
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2420 [inline]
 xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:2465 [inline]
 xfrm_resolve_and_create_bundle+0x723/0x2b00 net/xfrm/xfrm_policy.c:2760
 xfrm_lookup_with_ifid+0x268/0x1fd0 net/xfrm/xfrm_policy.c:3094
 xfrm_lookup net/xfrm/xfrm_policy.c:3223 [inline]
 xfrm_lookup_route+0x38/0x1a0 net/xfrm/xfrm_policy.c:3234
 rawv6_sendmsg+0xc1c/0x1710 net/ipv6/raw.c:933
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2446
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2500
 __sys_sendmmsg+0x27c/0x4a0 net/socket.c:2586
 __do_sys_sendmmsg net/socket.c:2615 [inline]
 __se_sys_sendmmsg net/socket.c:2612 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2612
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fb390aee749
RSP: 002b:00007fb38ed13038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fb390d45180 RCX: 00007fb390aee749
RDX: 00000000000002e9 RSI: 0000200000000480 RDI: 0000000000000008
RBP: 00007fb390b72f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb390d45218 R14: 00007fb390d45180 R15: 00007ffd96bc1388
 </TASK>
rcu: rcu_preempt kthread starved for 9939 jiffies! g16841 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:27008 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729