Re: [PATCH v1 3/3] x86/msr: Convert a native_wrmsr() use to native_wrmsrq()

[Ingo Molnar <mingo@xxxxxxxxxx>]

* Xin Li (Intel) <xin@xxxxxxxxx> wrote:

> Convert a native_wrmsr() use to native_wrmsrq() to zap meaningless type
> conversions when a u64 MSR value is splitted into two u32.
> 
> Signed-off-by: Xin Li (Intel) <xin@xxxxxxxxx>
> ---
>  arch/x86/coco/sev/core.c | 7 +------
>  1 file changed, 1 insertion(+), 6 deletions(-)
> 
> diff --git a/arch/x86/coco/sev/core.c b/arch/x86/coco/sev/core.c
> index ff82151f7718..b3ce6fc8b62d 100644
> --- a/arch/x86/coco/sev/core.c
> +++ b/arch/x86/coco/sev/core.c
> @@ -282,12 +282,7 @@ static inline u64 sev_es_rd_ghcb_msr(void)
>  
>  static __always_inline void sev_es_wr_ghcb_msr(u64 val)
>  {
> -     u32 low, high;
> -
> -     low  = (u32)(val);
> -     high = (u32)(val >> 32);
> -
> -     native_wrmsr(MSR_AMD64_SEV_ES_GHCB, low, high);
> +     native_wrmsrq(MSR_AMD64_SEV_ES_GHCB, val);

BTW., at this point we should probably just replace 
sev_es_wr_ghcb_msr() calls with direct calls to:

        native_wrmsrq(MSR_AMD64_SEV_ES_GHCB, ...);

as sev_es_wr_ghcb_msr() is now basically an open-coded native_wrmsrq().

Thanks,

        Ingo