Re: [PATCH 0/3] Change default machine type for aarch64 and riscv64
On Fri, Apr 14, 2023 at 03:14:46PM -0600, Jim Fehlig wrote:
On aarch64, the default CPU for machine type 'virt' is
'cortex-a15',
which works fine for <domain type='qemu'>, but fails for
type='kvm'
2023-04-14T21:03:03.392256Z qemu-system-aarch64: KVM is not supported for this guest CPU
type
Do we need to go a step further and define a default CPU (presumably
host-passthrough) for machine type 'virt' for kvm domains on aarch64?
Even for TCG, you're probably going to want to use something newer
and more featureful than the default. Heck, even on x86_64 the
default CPU model is pretty terrible and you really want to be using
either host-model or host-passthrough.
There's some movement in QEMU land when it comes to adding proper
support for CPU models on Arm. So I would leave things as they are
for now, in the hope that in the not-so-distant future we're going to
be able to make host-model work across both TCG and KVM.
--
Andrea Bolognani / Red Hat / Virtualization