Supported machines are:
microvm              microvm (i386)
pc-i440fx-zesty      Ubuntu 17.04 PC (i440FX + PIIX, 1996)
pc-i440fx-yakkety    Ubuntu 16.10 PC (i440FX + PIIX, 1996)
pc-i440fx-xenial     Ubuntu 16.04 PC (i440FX + PIIX, 1996)
pc-i440fx-wily       Ubuntu 15.04 PC (i440FX + PIIX, 1996)
pc-i440fx-trusty     Ubuntu 14.04 PC (i440FX + PIIX, 1996)
ubuntu               Ubuntu 21.10 PC (i440FX + PIIX, 1996) (alias of pc-i440fx-impish)
pc-i440fx-impish     Ubuntu 21.10 PC (i440FX + PIIX, 1996) (default)
pc-i440fx-impish-hpb Ubuntu 21.10 PC (i440FX + PIIX +host-phys-bits=true, 1996)
pc-i440fx-hirsute    Ubuntu 21.04 PC (i440FX + PIIX, 1996)
pc-i440fx-hirsute-hpb Ubuntu 21.04 PC (i440FX + PIIX +host-phys-bits=true, 1996)
pc-i440fx-groovy     Ubuntu 20.10 PC (i440FX + PIIX, 1996)
pc-i440fx-groovy-hpb Ubuntu 20.10 PC (i440FX + PIIX +host-phys-bits=true, 1996)
pc-i440fx-focal      Ubuntu 20.04 PC (i440FX + PIIX, 1996)
pc-i440fx-focal-hpb  Ubuntu 20.04 PC (i440FX + PIIX +host-phys-bits=true, 1996)
pc-i440fx-eoan       Ubuntu 19.10 PC (i440FX + PIIX, 1996)
pc-i440fx-eoan-hpb   Ubuntu 19.10 PC (i440FX + PIIX +host-phys-bits=true, 1996)
pc-i440fx-disco      Ubuntu 19.04 PC (i440FX + PIIX, 1996)
pc-i440fx-disco-hpb  Ubuntu 19.04 PC (i440FX + PIIX +host-phys-bits=true, 1996)
pc-i440fx-cosmic     Ubuntu 18.10 PC (i440FX + PIIX, 1996)
pc-i440fx-cosmic-hpb Ubuntu 18.10 PC (i440FX + PIIX +host-phys-bits=true, 1996)
pc-i440fx-bionic     Ubuntu 18.04 PC (i440FX + PIIX, 1996)
pc-i440fx-bionic-hpb Ubuntu 18.04 PC (i440FX + PIIX, +host-phys-bits=true, 1996)
pc-i440fx-artful     Ubuntu 17.10 PC (i440FX + PIIX, 1996)
pc                   Standard PC (i440FX + PIIX, 1996) (alias of pc-i440fx-6.0)
pc-i440fx-6.0        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-5.2        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-5.1        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-5.0        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-4.2        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-4.1        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-4.0        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-3.1        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-3.0        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.9        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.8        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.7        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.6        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.5        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.4        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.3        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.2        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.12       Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.11       Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.10       Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.1        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-2.0        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-1.7        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-1.6        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-1.5        Standard PC (i440FX + PIIX, 1996)
pc-i440fx-1.4        Standard PC (i440FX + PIIX, 1996)
pc-q35-zesty         Ubuntu 17.04 PC (Q35 + ICH9, 2009)
pc-q35-yakkety       Ubuntu 16.10 PC (Q35 + ICH9, 2009)
pc-q35-xenial        Ubuntu 16.04 PC (Q35 + ICH9, 2009)
ubuntu-q35           Ubuntu 21.10 PC (Q35 + ICH9, 2009) (alias of pc-q35-impish)
pc-q35-impish        Ubuntu 21.10 PC (Q35 + ICH9, 2009)
pc-q35-impish-hpb    Ubuntu 21.10 PC (Q35 + ICH9, +host-phys-bits=true, 2009)
pc-q35-hirsute       Ubuntu 21.04 PC (Q35 + ICH9, 2009)
pc-q35-hirsute-hpb   Ubuntu 21.04 PC (Q35 + ICH9, +host-phys-bits=true, 2009)
pc-q35-groovy        Ubuntu 20.10 PC (Q35 + ICH9, 2009)
pc-q35-groovy-hpb    Ubuntu 20.10 PC (Q35 + ICH9, +host-phys-bits=true, 2009)
pc-q35-focal         Ubuntu 20.04 PC (Q35 + ICH9, 2009)
pc-q35-focal-hpb     Ubuntu 20.04 PC (Q35 + ICH9, +host-phys-bits=true, 2009)
pc-q35-eoan          Ubuntu 19.10 PC (Q35 + ICH9, 2009)
pc-q35-eoan-hpb      Ubuntu 19.10 PC (Q35 + ICH9, +host-phys-bits=true, 2009)
pc-q35-disco         Ubuntu 19.04 PC (Q35 + ICH9, 2009)
pc-q35-disco-hpb     Ubuntu 19.04 PC (Q35 + ICH9, +host-phys-bits=true, 2009)
pc-q35-cosmic        Ubuntu 18.10 PC (Q35 + ICH9, 2009)
pc-q35-cosmic-hpb    Ubuntu 18.10 PC (Q35 + ICH9, +host-phys-bits=true, 2009)
pc-q35-bionic        Ubuntu 18.04 PC (Q35 + ICH9, 2009)
pc-q35-bionic-hpb    Ubuntu 18.04 PC (Q35 + ICH9, +host-phys-bits=true, 2009)
pc-q35-artful        Ubuntu 17.10 PC (Q35 + ICH9, 2009)
q35                  Standard PC (Q35 + ICH9, 2009) (alias of pc-q35-6.0)
pc-q35-6.0           Standard PC (Q35 + ICH9, 2009)
pc-q35-5.2           Standard PC (Q35 + ICH9, 2009)
pc-q35-5.1           Standard PC (Q35 + ICH9, 2009)
pc-q35-5.0           Standard PC (Q35 + ICH9, 2009)
pc-q35-4.2           Standard PC (Q35 + ICH9, 2009)
pc-q35-4.1           Standard PC (Q35 + ICH9, 2009)
pc-q35-4.0.1         Standard PC (Q35 + ICH9, 2009)
pc-q35-4.0           Standard PC (Q35 + ICH9, 2009)
pc-q35-3.1           Standard PC (Q35 + ICH9, 2009)
pc-q35-3.0           Standard PC (Q35 + ICH9, 2009)
pc-q35-2.9           Standard PC (Q35 + ICH9, 2009)
pc-q35-2.8           Standard PC (Q35 + ICH9, 2009)
pc-q35-2.7           Standard PC (Q35 + ICH9, 2009)
pc-q35-2.6           Standard PC (Q35 + ICH9, 2009)
pc-q35-2.5           Standard PC (Q35 + ICH9, 2009)
pc-q35-2.4           Standard PC (Q35 + ICH9, 2009)
pc-q35-2.12          Standard PC (Q35 + ICH9, 2009)
pc-q35-2.11          Standard PC (Q35 + ICH9, 2009)
pc-q35-2.10          Standard PC (Q35 + ICH9, 2009)
isapc                ISA-only PC
none                 empty machine
x-remote             Experimental remote machine