Re: [PATCH 1/7] hyperv: Detect Nested virtualization support for SVM

[Borislav Petkov]

On Wed, Apr 07, 2021 at 02:41:22PM +0000, Vineeth Pillai wrote:
> Detect nested features exposed by Hyper-V if SVM is enabled.
> 
> Signed-off-by: Vineeth Pillai <viremana@xxxxxxxxxxxxxxxxxxx>
> ---
>  arch/x86/kernel/cpu/mshyperv.c | 10 +++++++++-
>  1 file changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
> index 3546d3e21787..4d364acfe95d 100644
> --- a/arch/x86/kernel/cpu/mshyperv.c
> +++ b/arch/x86/kernel/cpu/mshyperv.c
> @@ -325,9 +325,17 @@ static void __init ms_hyperv_init_platform(void)
>  			ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b);
>  	}
>  
> -	if (ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED) {
> +	/*
> +	 * AMD does not need enlightened VMCS as VMCB is already a
> +	 * datastructure in memory. We need to get the nested
> +	 * features if SVM is enabled.
> +	 */
> +	if (boot_cpu_has(X86_FEATURE_SVM) ||

Pls use:

	    cpu_feature_enabled

here.

-- 
Regards/Gruss,
    Boris.

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