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Voluntary context switch within RCU read-side critical section!
WARNING: kernel/rcu/tree_plugin.h:332 at rcu_note_context_switch+0x859/0x19c0 kernel/rcu/tree_plugin.h:332, CPU#3: syz.0.17/5919
Modules linked in:
CPU: 3 UID: 0 PID: 5919 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:rcu_note_context_switch+0x859/0x19c0 kernel/rcu/tree_plugin.h:332
Code: c1 ea 03 80 3c 02 00 0f 85 9b 0b 00 00 48 8b 53 28 b9 01 00 00 00 4c 89 ef e8 03 d1 fe ff e9 1d f9 ff ff 48 8d 3d 97 cf 36 0f <67> 48 0f b9 3a e9 99 f8 ff ff 48 b8 00 00 00 00 00 fc ff df 48 8d
RSP: 0018:ffffc90006e1f130 EFLAGS: 00010002
RAX: 0000000000000001 RBX: ffff88806a73c540 RCX: ffffffff81eec4df
RDX: 0000000000000000 RSI: ffffffff8c400f00 RDI: ffffffff912608e0
RBP: ffff888024fc8000 R08: 0000000000000000 R09: fffffbfff22446b2
R10: ffffffff91223597 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888024fc84c4 R14: dffffc0000000000 R15: ffffffff91226964
FS:  000055556dd81500(0000) GS:ffff8880d60ea000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc277e73780 CR3: 000000003d9df000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 __schedule+0x277/0x6730 kernel/sched/core.c:7088
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0xdd/0x2c0 kernel/sched/core.c:7326
 netlink_broadcast_filtered+0xa76/0xf20 net/netlink/af_netlink.c:1553
 nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
 nlmsg_multicast include/net/netlink.h:1184 [inline]
 nlmsg_notify+0xb1/0x290 net/netlink/af_netlink.c:2599
 __ip6_del_rt_siblings net/ipv6/route.c:4080 [inline]
 ip6_route_del+0x1109/0x1d50 net/ipv6/route.c:4220
 inet6_rtm_delroute+0x27d/0x3b0 net/ipv6/route.c:5657
 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0xa4d/0xbe0 net/socket.c:2684
 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2738
 __sys_sendmsg+0x160/0x210 net/socket.c:2770
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc277f9de59
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:00007fffe1da7618 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fc278225fa0 RCX: 00007fc277f9de59
RDX: 0000000000000000 RSI: 0000200000000280 RDI: 0000000000000004
RBP: 00007fc278033e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc278225fac R14: 00007fc278225fa0 R15: 00007fc278225fa0
 </TASK>
----------------
Code disassembly (best guess):
   0:	c1 ea 03             	shr    $0x3,%edx
   3:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   7:	0f 85 9b 0b 00 00    	jne    0xba8
   d:	48 8b 53 28          	mov    0x28(%rbx),%rdx
  11:	b9 01 00 00 00       	mov    $0x1,%ecx
  16:	4c 89 ef             	mov    %r13,%rdi
  19:	e8 03 d1 fe ff       	call   0xfffed121
  1e:	e9 1d f9 ff ff       	jmp    0xfffff940
  23:	48 8d 3d 97 cf 36 0f 	lea    0xf36cf97(%rip),%rdi        # 0xf36cfc1
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	e9 99 f8 ff ff       	jmp    0xfffff8cd
  34:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  3b:	fc ff df
  3e:	48                   	rex.W
  3f:	8d                   	.byte 0x8d