Re: [PATCH v8 16/40] KVM: SVM: Define sev_features and vmpl field in the VMSA

[Venu Busireddy]

On 2021-12-10 09:43:08 -0600, Brijesh Singh wrote:
> The hypervisor uses the sev_features field (offset 3B0h) in the Save State
> Area to control the SEV-SNP guest features such as SNPActive, vTOM,
> ReflectVC etc. An SEV-SNP guest can read the SEV_FEATURES fields through
> the SEV_STATUS MSR.
> 
> While at it, update the dump_vmcb() to log the VMPL level.
> 
> See APM2 Table 15-34 and B-4 for more details.
> 
> Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>

Reviewed-by: Venu Busireddy <venu.busireddy@xxxxxxxxxx>

> ---
>  arch/x86/include/asm/svm.h | 6 ++++--
>  arch/x86/kvm/svm/svm.c     | 4 ++--
>  2 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
> index d3277486a6c0..c3fad5172584 100644
> --- a/arch/x86/include/asm/svm.h
> +++ b/arch/x86/include/asm/svm.h
> @@ -238,7 +238,8 @@ struct vmcb_save_area {
>  	struct vmcb_seg ldtr;
>  	struct vmcb_seg idtr;
>  	struct vmcb_seg tr;
> -	u8 reserved_1[43];
> +	u8 reserved_1[42];
> +	u8 vmpl;
>  	u8 cpl;
>  	u8 reserved_2[4];
>  	u64 efer;
> @@ -303,7 +304,8 @@ struct vmcb_save_area {
>  	u64 sw_exit_info_1;
>  	u64 sw_exit_info_2;
>  	u64 sw_scratch;
> -	u8 reserved_11[56];
> +	u64 sev_features;
> +	u8 reserved_11[48];
>  	u64 xcr0;
>  	u8 valid_bitmap[16];
>  	u64 x87_state_gpa;
> diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> index 65707bee208d..d3a6356fa1af 100644
> --- a/arch/x86/kvm/svm/svm.c
> +++ b/arch/x86/kvm/svm/svm.c
> @@ -3290,8 +3290,8 @@ static void dump_vmcb(struct kvm_vcpu *vcpu)
>  	       "tr:",
>  	       save01->tr.selector, save01->tr.attrib,
>  	       save01->tr.limit, save01->tr.base);
> -	pr_err("cpl:            %d                efer:         %016llx\n",
> -		save->cpl, save->efer);
> +	pr_err("vmpl: %d   cpl:  %d               efer:          %016llx\n",
                                                       ^
Extra space?

> +	       save->vmpl, save->cpl, save->efer);
>  	pr_err("%-15s %016llx %-13s %016llx\n",
>  	       "cr0:", save->cr0, "cr2:", save->cr2);
>  	pr_err("%-15s %016llx %-13s %016llx\n",
> -- 
> 2.25.1
>