симптомы:
[ 2.961074] platform regulatory.0: Direct firmware load for regulatory.db failed with error -2
[ 2.961077] cfg80211: failed to load regulatory.db
...
[ 3.094568] brcmfmac 0000:3a:00.0: Direct firmware load for brcm/brcmfmac4350-pcie.txt failed with error -2
В VirtualBox машины просто не стартуют, в dmesg никаких ошибок относящихся к virtual-box модулям
