On Wed, Aug 31, 2022 at 15:11:41 +0100, Daniel P. Berrangé wrote: > On Wed, Aug 31, 2022 at 02:30:52PM +0200, Jiri Denemark wrote: > > On Wed, Aug 31, 2022 at 09:22:16 +0000, Liu Yiding wrote: > > > Add A64FX as a supported cpu model. > > > > > > Signed-off-by: Liu Yiding <liuyd.fnst@xxxxxxxxxxx> > > > --- > > > src/cpu_map/arm_A64FX.xml | 6 ++++++ > > > src/cpu_map/arm_vendors.xml | 1 + > > > src/cpu_map/index.xml | 3 +++ > > > src/cpu_map/meson.build | 1 + > > > 4 files changed, 11 insertions(+) > > > create mode 100644 src/cpu_map/arm_A64FX.xml > > > > CPU detection for ARM is a bit awkward and not very useful in practice. > > It will (in some cases) report the host CPU in host capabilities, but > > that's it. The CPU from host capabilities cannot really be used in > > general for specifying a guest CPU in domain XML and it would not even > > make a lot of sense as I believe the only really supported CPU for KVM > > is "host" (mode="host-passthrough" in domain XML). > > This still lets it be used for a guest with TCG, which has no requirement > to use 'host'. The host CPU is irrelevant for TCG and libvirt on ARM has always allowed any CPU model to be used, even those that are not in cpu_map. And since a lot of the ARM CPUs in cpu_map do not match anything in QEMU anyway, which is the reason why host CPU detection on ARM is mostly a cosmetic thing. > > I'm not saying the patch is wrong, I'm just trying to make sure you > > don't expect something more from implementing this patch. Jirka
