Re: [PATCH v3 4/4] target/i386: Add notes for versioned CPU models

[Eduardo Habkost]

On Wed, Feb 12, 2020 at 04:13:28PM +0800, Tao Xu wrote:
> Add which features are added or removed in this version. Remove the
> changed model-id in versioned CPU models, to keep the model name
> unchanged at /proc/cpuinfo inside the VM.
> 
> Signed-off-by: Tao Xu <address@hidden>
> ---
> 
> Changes in v2:
>     - correct the note of Cascadelake v3 (Xiaoyao)
> ---
>  target/i386/cpu.c | 54 ++++++++++++++++++++++-------------------------
>  1 file changed, 25 insertions(+), 29 deletions(-)
> 
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 81a039beb6..739ef4ce91 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -2278,10 +2278,9 @@ static X86CPUDefinition builtin_x86_defs[] = {
>              {
>                  .version = 2,
>                  .alias = "Nehalem-IBRS",
> +                .note = "IBRS",
>                  .props = (PropValue[]) {
>                      { "spec-ctrl", "on" },
> -                    { "model-id",
> -                      "Intel Core i7 9xx (Nehalem Core i7, IBRS update)" },
>                      { /* end of list */ }

Changing model-id is guest-visible, so we can't do this.  The
same applies to the other models where model-id is being removed.

I suggest using the .note property only on the CPU model versions
that don't have custom model-id set yet, or when existing
information on model-id is incomplete.

For future CPU model versions, we can start using only .note and
stop changing model-id.

-- 
Eduardo