Re: [PATCH 1/4] kvm: svm: Streamline VMSA setting for VCPUs

On Thu, Jun 11, 2026, J=C3=B6rg R=C3=B6del wrote:
> From: Joerg Roedel <[email protected]>
>=20
> Streamline the VMSA setting state of vcpus, where a VMSA can be either
> KVM-allocated or guest-provided. This consolidates the various
> tracking state around VMSAs.

This needs to be split up into distinct logic changes.  There are renames, =
there
are tracking changes, there is code movement, and who knows what else, all =
bundled
together.  And the changelog is little more than "consolidate stuff".

>=20
> Signed-off-by: Joerg Roedel <[email protected]>
> ---
>  arch/x86/kvm/svm/sev.c | 301 ++++++++++++++++++++++++++++-------------
>  arch/x86/kvm/svm/svm.h |  31 ++++-
>  2 files changed, 237 insertions(+), 95 deletions(-)

+180 lines of code doesn't scream "streamline" to me.

> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
> index 6c6a6d663e29..9b1280222e20 100644
> --- a/arch/x86/kvm/svm/sev.c
> +++ b/arch/x86/kvm/svm/sev.c
> @@ -147,6 +147,9 @@ static bool sev_snp_guest(struct kvm *kvm)
>  }
> =20
>  static int snp_decommission_context(struct kvm *kvm);
> +static int kvm_rmp_make_shared(struct kvm *kvm, u64 pfn, enum pg_level l=
evel);
> +static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va);
> +static int snp_page_reclaim(struct kvm *kvm, u64 pfn);
> =20
>  struct enc_region {
>  	struct list_head list;
> @@ -156,6 +159,173 @@ struct enc_region {
>  	unsigned long size;
>  };
> =20
> +static void *sev_es_vmsa_ref(struct kvm_vcpu *vcpu)
> +{
> +	struct vcpu_svm *svm =3D to_svm(vcpu);
> +	void *vmsa =3D NULL;
> +
> +	if (svm->sev_es.vmsa.vmsa_state =3D=3D VMSA_SHARED) {

Unnecessary curly braces.

> +		vmsa =3D page_address(svm->sev_es.vmsa.vmsa_page);
> +	}
> +
> +	return vmsa;
> +}

...

> diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
> index 5137416be593..3d4799f09b23 100644
> --- a/arch/x86/kvm/svm/svm.h
> +++ b/arch/x86/kvm/svm/svm.h
> @@ -240,9 +240,29 @@ struct svm_nested_state {
>  	bool force_msr_bitmap_recalc;
>  };
> =20
> +enum vmsa_state {
> +	/* No VMSA set */
> +	VMSA_NONE,
> +	/* VMSA allocated by KVM - Shared in RMP (if applicable) */
> +	VMSA_SHARED,
> +	/* VMSA allocated by KVM - Guest-private in RMP (SEV-SNP only) */
> +	VMSA_PRIVATE,
> +	/* Guest-owned VMSA */
> +	VMSA_GUEST,
> +};

I am strongly against this tracking.  AFAICT, every case is completely redu=
ndant
with other information that *must* be tracked.=20