syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-....: (6 ticks this GP) idle=91f/1/0x4000000000000002 softirq=99547/99547 fqs=2096 
	(detected by 1, t=10503 jiffies, g=141201, q=1179)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 1367 Comm: syz.1.8753 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:mark_held_locks kernel/locking/lockdep.c:4181 [inline]
RIP: 0010:__trace_hardirqs_on_caller kernel/locking/lockdep.c:4211 [inline]
RIP: 0010:lockdep_hardirqs_on_prepare+0x272/0x770 kernel/locking/lockdep.c:4278
Code: 00 48 ba 00 00 00 00 00 fc ff df 85 c0 0f 84 a2 01 00 00 41 0f b6 04 16 84 c0 75 5b 49 ff c5 48 63 03 49 83 c7 28 49 83 c4 28 <49> 39 c5 7c 95 eb 66 48 c7 c7 60 de 1e 8c 4c 89 ee e8 28 3e a7 02
RSP: 0018:ffffc90000007640 EFLAGS: 00000082
RAX: 0000000000000007 RBX: ffff8880223da8a8 RCX: ffffffff815dca24
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff901d5158
RBP: ffffc900000076f8 R08: ffffffff901d515f R09: 1ffffffff203aa2b
R10: dffffc0000000000 R11: fffffbfff203aa2c R12: ffff8880223da998
R13: 0000000000000005 R14: 1ffff1100447b515 R15: ffff8880223da978
FS:  00007f8c0038a6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8c00348d58 CR3: 000000007aad0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 trace_hardirqs_on+0x67/0x80 kernel/trace/trace_preemptirq.c:49
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 32 e1 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900000077c0 EFLAGS: 00000206
RAX: 97c6c9f1854a9800 RBX: 1ffff92000000efc RCX: 97c6c9f1854a9800
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: ffffffff8a79fe00
RBP: ffffc900000078a0 R08: ffffffff901d51c7 R09: 1ffffffff203aa38
R10: dffffc0000000000 R11: fffffbfff203aa39 R12: ffffffff8c323000
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 ndisc_send_skb+0xde0/0x1500 net/ipv6/ndisc.c:521
 addrconf_rs_timer+0x2d1/0x630 net/ipv6/addrconf.c:3956
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x208/0x400 kernel/locking/lockdep.c:5627
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3d 04 f8 0f 85 f1 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 43 c7 44 3d 08 00 00 00 00 65 48 8b 04
RSP: 0018:ffffc9000330eec0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 97c6c9f1854a9800
RDX: 0000000000000000 RSI: ffffffff8a2b3aa0 RDI: ffffffff8a79fe00
RBP: ffffc9000330efd8 R08: dffffc0000000000 R09: 1ffffffff203aa2b
R10: dffffc0000000000 R11: fffffbfff203aa2c R12: ffffc900017e6988
R13: 1ffff92000661de4 R14: 0000000000000246 R15: dffffc0000000000
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:364 [inline]
 inet_diag_dump_icsk+0x372/0x14c0 net/ipv4/inet_diag.c:1038
 __inet_diag_dump+0x1f6/0x380 net/ipv4/inet_diag.c:1179
 inet_diag_dump_compat+0x17e/0x220 net/ipv4/inet_diag.c:1288
 netlink_dump+0x694/0xcf0 net/netlink/af_netlink.c:2283
 __netlink_dump_start+0x523/0x700 net/netlink/af_netlink.c:2386
 netlink_dump_start include/linux/netlink.h:258 [inline]
 inet_diag_rcv_msg_compat+0x207/0x420 net/ipv4/inet_diag.c:1323
 sock_diag_rcv_msg+0x164/0x3e0 net/core/sock_diag.c:-1
 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507
 sock_diag_rcv+0x26/0x40 net/core/sock_diag.c:276
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445
 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499
 __sys_sendmsg net/socket.c:2528 [inline]
 __do_sys_sendmsg net/socket.c:2537 [inline]
 __se_sys_sendmsg+0x1af/0x290 net/socket.c:2535
 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: 0033:0x7f8c02130dd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8c0038a028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f8c023a9fa0 RCX: 00007f8c02130dd9
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000007
RBP: 00007f8c021c6d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8c023aa038 R14: 00007f8c023a9fa0 R15: 00007ffc2e0d4918
 </TASK>