bisecting fixing commit since c10b57a567e4333b9fdf60b5ec36de9859263ca2 building syzkaller on 3f3c557402456696073f79aafa65b4d7fa2b8794 testing commit c10b57a567e4333b9fdf60b5ec36de9859263ca2 with gcc (GCC) 8.1.0 kernel signature: 0adb341a9a403c78e975ab27f08e8d3143b8830119b2811764547d3b5d474b81 all runs: crashed: BUG: looking up invalid subclass: 8 testing current HEAD 14b58326976de6ef3998eefec1dd7f8b38b97a75 testing commit 14b58326976de6ef3998eefec1dd7f8b38b97a75 with gcc (GCC) 8.1.0 kernel signature: e56a6a3dee96f050d12d2bbf553d5eb151c99a29b57c56f8406354e069cf46b0 all runs: crashed: BUG: looking up invalid subclass: 8 revisions tested: 2, total time: 26m8.214929481s (build: 18m10.532819752s, test: 6m24.058830897s) the crash still happens on HEAD commit msg: Linux 4.14.193 crash: BUG: looking up invalid subclass: 8 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! BUG: looking up invalid subclass: 8 turning off the locking correctness validator. CPU: 0 PID: 9933 Comm: syz-executor.3 Not tainted 4.14.193-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xf7/0x13b lib/dump_stack.c:58 look_up_lock_class kernel/locking/lockdep.c:673 [inline] register_lock_class+0x5b7/0x1cd0 kernel/locking/lockdep.c:756 __lockdep_init_map+0x2b8/0x550 kernel/locking/lockdep.c:3277 lockdep_init_map+0x9/0x10 kernel/locking/lockdep.c:3287 vlan_dev_set_lockdep_class net/8021q/vlan_dev.c:509 [inline] vlan_dev_init+0x75d/0xba0 net/8021q/vlan_dev.c:604 register_netdevice+0x252/0xe50 net/core/dev.c:7589 register_vlan_dev+0x24f/0x650 net/8021q/vlan.c:168 vlan_newlink+0x366/0x4d0 net/8021q/vlan_netlink.c:165 rtnl_newlink+0xc2b/0x13a0 net/core/rtnetlink.c:2728 rtnetlink_rcv_msg+0x34c/0x9e0 net/core/rtnetlink.c:4316 netlink_rcv_skb+0x12f/0x3b0 net/netlink/af_netlink.c:2433 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4328 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x40b/0x600 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x730/0xbd0 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:656 ___sys_sendmsg+0x625/0x920 net/socket.c:2062 __sys_sendmsg+0xc1/0x140 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0xd/0x20 net/socket.c:2103 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45c909 RSP: 002b:00007fd314704c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fd3147056d4 RCX: 000000000045c909 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000004 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009fe R14: 00000000004ccc24 R15: 000000000076bf0c