miihub: loaded; hw.miihub_fire=1 panics, hw.miihub_fixcheck=1 validates the fix shape
miihub-fix: ifmedia_init (EMPTY list) + fixed hub walk (empty -> add IFM_ETHER|IFM_AUTO -> ifmedia_set)
miihub-fix: survived; ifm_cur=0xfffff8008d5a10c0 media=0x20
miihub-fix: ifm_cur->ifm_media=0x20 (service deref safe)
miihub: ifmedia_init (EMPTY ifm_list -- all PHYs took the 'no media present' branch, parent added nothing)
miihub: running miibus_mediainit walk verbatim (mii.c:238-244)
ifmedia_set: no match for 0x0/0xfffffff
panic: ifmedia_set
cpuid = 2
Trace beginning at frame 0xfffff80118443758
ifmedia_set() at ifmedia_set+0x53 0xffffffff807432b3 
ifmedia_set() at ifmedia_set+0x53 0xffffffff807432b3 
miihub_fire() at miihub_fire+0x8c 0xffffffff8260024c 
sysctl_root.isra.5() at sysctl_root.isra.5+0x166 0xffffffff80683d06 
userland_sysctl() at userland_sysctl+0x111 0xffffffff806840a1 
sys___sysctl() at sys___sysctl+0x74 0xffffffff80684204 
Debugger("panic")

CPU2 stopping CPUs: 0x0000003b
 stopped
Stopped at      Debugger+0x7c:  movb    $0,0xbdaf09(%rip)
db>