Re: Improve default machine type selection

On 3/16/23 11:56, Jim Fehlig wrote: > On 3/15/23 08:40, Ján Tomko wrote: > > On a Monday in 2023, Jim Fehlig wrote: > > > If an explicit machine type is not specified in the VM config, > > > the qemu driver will select the first machine type in the list > > > of machine types for the specified accelerator. See > > > virQEMUCapsGetPreferredMachine > > > > > > https://gitlab.com/libvirt/libvirt/-/blob/master/src/qemu/qemu_capabiliti... > > > > > > On my test machines, this works reasonably well for x86_64 where > > > the first machine type is pc-i440fx-7.1. But for aarch64, the > > > first machine is integratorcp, which is not very useful with > > > maxCpus=1 and other limitations. > > > > Is it possible to run such machine with libvirt? > > I just did a quick check with libvirt 9.1.0 (qemu is a bit older, at 7.1.0): > > # cat test.xml > <domain type='kvm'> >   <name>test</name> >   <memory unit='KiB'>2097152</memory> >   <vcpu placement='static'>1</vcpu> >   <os> >     <type>hvm</type> >     <loader readonly='yes' > type='pflash'>/usr/share/qemu/aavmf-aarch64-code.bin</loader> >     <nvram template='/usr/share/qemu/aavmf-aarch64-vars.bin'/> >     <boot dev='hd'/> >   </os> >   <clock offset='utc'/> >   <on_poweroff>destroy</on_poweroff> >   <on_reboot>restart</on_reboot> >   <on_crash>destroy</on_crash> >   <devices> >     <emulator>/usr/bin/qemu-system-aarch64</emulator> >     <disk type='file' device='disk'> >       <driver name='qemu' type='qcow2' discard='unmap'/> >       <source file='/var/lib/libvirt/images/test.qcow2'/> >       <target dev='vda' bus='virtio'/> >     </disk> >   </devices> > </domain> > # virsh create test.xml > error: Failed to create domain from test.xml > error: internal error: Unexpected enum value 0 for virDomainDeviceAddressType > > I don't _think_ it's a downstream bug, nor fixed in git in the meantime. > It appears running the old integratorcp machine with libivrt is not > possible. I trimmed the config to remove things like virtio devices that are not supported by the default machine type, but still it does not work with libvirt: # cat test.xml <domain type='kvm'> <name>test</name> <memory unit='KiB'>2097152</memory> <vcpu placement='static'>1</vcpu> <os> <type>hvm</type> </os> <devices> <emulator>/usr/bin/qemu-system-aarch64</emulator> </devices> </domain> # virsh create test.xml error: Failed to create domain from test.xml error: internal error: process exited while connecting to monitor: 2023-04-05T20:36:19.564896Z qemu-system-aarch64: Property 'integratorcp-machine.acpi' not found