syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P16291/1:b..l
	(detected by 0, t=10502 jiffies, g=102865, q=14 ncpus=2)
task:syz.2.3871      state:R  running task     stack:24312 pid:16291 ppid:13298  flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__ip_dev_find+0x0/0x5c0 net/ipv4/devinet.c:154
Code: e9 42 ff ff ff 89 d9 80 e1 07 38 c1 0f 8c 5a ff ff ff 48 89 df e8 a0 16 c7 f8 e9 4d ff ff ff cc cc cc cc cc cc cc cc cc cc cc <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 20 01
RSP: 0018:ffffc9000a34f090 EFLAGS: 00000246
RAX: 0000000000000002 RBX: 000000000100007f RCX: 0000000000040000
RDX: 0000000000000000 RSI: 000000000100007f RDI: ffff888021f3b880
RBP: 0000000000000000 R08: ffffffff8902c463 R09: fffffbfff2093845
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc9000a34f180
R13: 0000000000000000 R14: ffffc9000a34f3a0 R15: dffffc0000000000
 ip_route_output_key_hash_rcu+0x196/0x2380 net/ipv4/route.c:2705
 ip_route_output_key_hash+0x207/0x360 net/ipv4/route.c:2641
 __ip_route_output_key include/net/route.h:137 [inline]
 ip_route_output_flow+0x25/0x130 net/ipv4/route.c:2871
 udp_sendmsg+0x1846/0x2ad0 net/ipv4/udp.c:1247
 udpv6_sendmsg+0xd24/0x30e0 net/ipv6/udp.c:1410
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x5a5/0x8f0 net/socket.c:2514
 ___sys_sendmsg net/socket.c:2568 [inline]
 __sys_sendmmsg+0x3ab/0x730 net/socket.c:2654
 __do_sys_sendmmsg net/socket.c:2683 [inline]
 __se_sys_sendmmsg net/socket.c:2680 [inline]
 __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2680
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fae1d775f19
RSP: 002b:00007fae1e4bf048 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fae1d906110 RCX: 00007fae1d775f19
RDX: 0400000000000172 RSI: 0000000020003cc0 RDI: 0000000000000003
RBP: 00007fae1d7e4e68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000004000300 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fae1d906110 R15: 00007fff2f825c88
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10542 jiffies! g102865 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=59781
rcu: rcu_preempt kthread starved for 10543 jiffies! g102865 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:26144 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 schedule+0xbf/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.100-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline]
RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:112 [inline]
RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567
Code: 0b f5 f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 f4 c9 fb f6 0f 1f 44 00 00 e8 4a 07 f5 f6 0f 00 2d 63 d5 b1 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 3b 8f 4c f7
RSP: 0018:ffffffff8ce07b20 EFLAGS: 000002d3
RAX: ffffffff8a959336 RBX: 0000000000000000 RCX: ffffffff8cebd800
RDX: 0000000000000000 RSI: ffffffff8aec0240 RDI: ffffffff8b3d48a0
RBP: ffffffff8ce07bb0 R08: ffffffff8a959318 R09: fffffbfff19d7b01
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff19c0f64
R13: ffff888016bc1804 R14: ffffffff8ce07b40 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000005e893000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:704
 cpuidle_enter_state+0x516/0xf80 drivers/cpuidle/cpuidle.c:239
 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x3ce/0x680 kernel/sched/idle.c:303
 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:401
 rest_init+0x2da/0x300 init/main.c:733
 arch_call_rest_init+0xa/0xa init/main.c:893
 start_kernel+0x496/0x53f init/main.c:1140
 secondary_startup_64_no_verify+0xcf/0xdb
 </TASK>