syzbot

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2656 jiffies s: 38349 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 13038 Comm: syz-executor.5 Not tainted 6.4.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:__list_add_valid+0x39/0xf0 lib/list_debug.c:27
Code: f6 0f 84 8a 00 00 00 49 89 d6 48 85 d2 0f 84 8c 00 00 00 49 89 f4 49 89 ff 49 bd 00 00 00 00 00 fc ff df 49 8d 5e 08 48 89 d8 <48> c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 44 84 aa fd 48 8b 13
RSP: 0000:ffffc900001e02f8 EFLAGS: 00000282
RAX: ffff8880221862e8 RBX: ffff8880221862e8 RCX: dffffc0000000000
RDX: ffff8880221862e0 RSI: ffff8880221862e0 RDI: ffff88803de99730
RBP: ffff8880221862e0 R08: ffffffff88d11608 R09: ffffffff88ba5cae
R10: 0000000000000002 R11: ffff88801f599dc0 R12: ffff8880221862e0
R13: dffffc0000000000 R14: ffff8880221862e0 R15: ffff88803de99730
FS:  00007f11c7671700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d331000 CR3: 000000002b536000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __list_add include/linux/list.h:69 [inline]
 list_add_tail include/linux/list.h:102 [inline]
 list_move_tail include/linux/list.h:230 [inline]
 fq_pie_qdisc_dequeue+0x3f5/0xa40 net/sched/sch_fq_pie.c:248
 dequeue_skb net/sched/sch_generic.c:292 [inline]
 qdisc_restart net/sched/sch_generic.c:397 [inline]
 __qdisc_run+0x26e/0x20a0 net/sched/sch_generic.c:415
 __dev_xmit_skb net/core/dev.c:3868 [inline]
 __dev_queue_xmit+0x1397/0x38b0 net/core/dev.c:4210
 neigh_output include/net/neighbour.h:544 [inline]
 ip6_finish_output2+0xf80/0x1560 net/ipv6/ip6_output.c:134
 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
 ip6_finish_output+0x6b0/0xa80 net/ipv6/ip6_output.c:206
 dst_output include/net/dst.h:458 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 ndisc_send_skb+0xb08/0x1390 net/ipv6/ndisc.c:508
 addrconf_rs_timer+0x35b/0x620 net/ipv6/addrconf.c:3936
 call_timer_fn+0x178/0x580 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x64f/0x860 kernel/time/timer.c:2022
 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035
 __do_softirq+0x2ab/0x908 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x159/0x240 kernel/softirq.c:650
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:207 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:239 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:test_ti_thread_flag include/linux/thread_info.h:118 [inline]
RIP: 0010:test_tsk_thread_flag include/linux/sched.h:2050 [inline]
RIP: 0010:task_sigpending include/linux/sched/signal.h:389 [inline]
RIP: 0010:signal_pending+0x72/0xa0 include/linux/sched/signal.h:401
Code: 00 00 02 00 4c 21 e6 31 ff e8 ea d9 2a f8 4d 21 e5 75 34 e8 a0 d5 2a f8 48 89 df be 08 00 00 00 e8 53 ac 82 f8 43 80 3c 37 00 <74> 08 48 89 df e8 84 aa 82 f8 48 8b 03 c1 e8 02 83 e0 01 5b 41 5c
RSP: 0000:ffffc900054a76d0 EFLAGS: 00000246
RAX: ffffffff8960a901 RBX: ffff88801f599dc0 RCX: ffffffff8960a99d
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88801f599dc0
RBP: ffffc900054a78b0 R08: dffffc0000000000 R09: ffffed1003eb33b9
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000004002
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff11003eb33b8
 unix_dgram_sendmsg+0x13a7/0x2050 net/unix/af_unix.c:2051
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg net/socket.c:747 [inline]
 ____sys_sendmsg+0x58f/0x890 net/socket.c:2503
 ___sys_sendmsg net/socket.c:2557 [inline]
 __sys_sendmmsg+0x3af/0x730 net/socket.c:2643
 __do_sys_sendmmsg net/socket.c:2672 [inline]
 __se_sys_sendmmsg net/socket.c:2669 [inline]
 __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2669
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f11c688c169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f11c7671168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f11c69ac050 RCX: 00007f11c688c169
RDX: 0000000000000318 RSI: 00000000200bd000 RDI: 0000000000000004
RBP: 00007f11c68e7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdecd956df R14: 00007f11c7671300 R15: 0000000000022000
 </TASK>