Re: [PATCH] Modify virCPUarmCompare to perform compare actions
On Fri, Aug 21, 2020 at 10:20:15 +0800, Zhenyu Zheng wrote:
Modify virCPUarmCompare in cpu_arm.c to perform
actual compare actions. Compare host cpu vendor
and model info with guest cpu as initial implementation,
as most ARM clouds uses host-passthrogh mode.
In addition to the low-level coding issues found by Daniel Henrique
Barboza, I'd like to ask some high level questions...
What is the point in making this patch (except for copying the logic
from x86 CPU driver, which mostly does not fit ARM world very well)?
As you say, most ARM clouds use host-passthrough, so why would CPU
comparison be needed at all? Host-passthrough CPU is by definition
compatible with any host CPU as it asks for the host CPU itself.
Also IIRC the CPU model names as advertised by libvirt in host
capabilities are only useful for identifying the host CPU, but they
cannot be directly pass to QEMU. As such, you can't use these models
when defining a CPU in a domain XML.
That said, I doubt this patch is useful at all.
Jirka