Re: [PATCH 3/3] x86/ucode: Introduce ucode=allow-same for testing purposes

[Jürgen Groß <jgross@xxxxxxxx>]

On 26.10.20 18:25, Andrew Cooper wrote:
> Many CPUs will actually reload microcode when offered the same version as
> currently loaded.  This allows for easy testing of the late microcode loading
> path.
>
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> ---
> CC: Jan Beulich <JBeulich@xxxxxxxx>
> CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
> CC: Wei Liu <wl@xxxxxxx>
> CC: Juergen Gross <jgross@xxxxxxxx>
> CC: Igor Druzhinin <igor.druzhinin@xxxxxxxxxx>
>
> I was hoping to make this a runtime parameter, but I honestly can't figure out
> the new HYPFS-only infrastructure is supposed to work.
For your use case have a look into xen/arch/x86/hvm/vmx/vmcs.c how the
"ept" runtime parameter is handled.

This is a similar case where one sub-option can be modified at runtime.


Juergen