issuing SIOCDLIFADDR(lo0, 0.248.255.255) ...
(ssh session hung; serial console shows:)
Fatal trap 12: page fault while in kernel mode
cpuid = 0; lapic id = 0
fault virtual address	= 0xe4
fault code		= supervisor write data, page not present
instruction pointer	= 0x8:0xfffff8004f308f46
stack pointer	        = 0x10:0xfffff8008d1f8a70
frame pointer	        = 0x10:0xfffff8004f308f28
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= Idle
current thread          = pri 12 
kernel: type 12 trap, code=2

CPU0 stopping CPUs: 0x0000003e
 stopped
Stopped at      -0x7ffb0cf70ba: addb    %al,(%rax)
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