plugging in a USB WIFI dongle I got this; unclear if it was from this one or another one which got toggled down/up ... fairly recent HEAD of sometime the last two weeks. I thought these panics were gone .. panic: starting DAD on non-tentative address 0xfffff80003990600 cpuid = 1 time = 1502195081 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe003b653690 vpanic() at vpanic+0x182/frame 0xfffffe003b6536e0 panic() at panic+0x43/frame 0xfffffe003b653740 nd6_dad_start() at nd6_dad_start+0x3bb/frame 0xfffffe003b6537e0 in6_if_up() at in6_if_up+0x62/frame 0xfffffe003b653820 if_up() at if_up+0x69/frame 0xfffffe003b653850 ifhwioctl() at ifhwioctl+0xbf8/frame 0xfffffe003b6538d0 ifioctl() at ifioctl+0x3ac/frame 0xfffffe003b6539a0 kern_ioctl() at kern_ioctl+0x27b/frame 0xfffffe003b653a00 sys_ioctl() at sys_ioctl+0x127/frame 0xfffffe003b653ad0 amd64_syscall() at amd64_syscall+0x140/frame 0xfffffe003b653bf0 fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe003b653bf0 --- syscall (54, FreeBSD ELF64, sys_ioctl), rip = 0x80047cd8a, rsp = 0x7fffffffe258, rbp = 0x7fffffffe2b0 --- KDB: enter: panic [ thread pid 42874 tid 100086 ] Stopped at kdb_enter+0x37: movq $0,0x10c9ad6(%rip) db> show reg cs 0x20 ds 0x3b ll+0x1a es 0x3b ll+0x1a fs 0x13 gs 0x1b ss 0x28 ll+0x7 rax 0x12 rcx 0x80 ll+0x5f rdx 0xfffffe003b653580 rbx 0xffffffff8123674c rsp 0xfffffe003b653680 rbp 0xfffffe003b653690 rsi 0x80 ll+0x5f rdi 0xffffffff81c8e6d8 cnputs_mtx r8 0x10 r9 0xffffffff80c15ae0 putchar r10 0xffffffff81afca10 vga_conssoftc r11 0x10 r12 0x1 r13 0xfffff80003990600 r14 0 r15 0xfffffe0032deb000 rip 0xffffffff80c0f3b7 kdb_enter+0x37 rflags 0x82 ll+0x61 kdb_enter+0x37: movq $0,0x10c9ad6(%rip)