From:   Zhi Wang <zhi.wang.linux@gmail.com>
Date:   Wed, 1 Mar 2023 12:45:16 +0200
To:     Michael Roth <michael.roth@amd.com>
Cc:     <kvm@vger.kernel.org>, <linux-coco@lists.linux.dev>,
        <linux-mm@kvack.org>, <linux-crypto@vger.kernel.org>,
        <x86@kernel.org>, <linux-kernel@vger.kernel.org>,
        <tglx@linutronix.de>, <mingo@redhat.com>, <jroedel@suse.de>,
        <thomas.lendacky@amd.com>, <hpa@zytor.com>, <ardb@kernel.org>,
        <pbonzini@redhat.com>, <seanjc@google.com>, <vkuznets@redhat.com>,
        <jmattson@google.com>, <luto@kernel.org>,
        <dave.hansen@linux.intel.com>, <slp@redhat.com>,
        <pgonda@google.com>, <peterz@infradead.org>,
        <srinivas.pandruvada@linux.intel.com>, <rientjes@google.com>,
        <dovmurik@linux.ibm.com>, <tobin@ibm.com>, <bp@alien8.de>,
        <vbabka@suse.cz>, <kirill@shutemov.name>, <ak@linux.intel.com>,
        <tony.luck@intel.com>, <marcorr@google.com>,
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        <alpergun@google.com>, <dgilbert@redhat.com>, <jarkko@kernel.org>,
        <ashish.kalra@amd.com>, <nikunj.dadhania@amd.com>,
        Brijesh Singh <brijesh.singh@amd.com>
Subject: Re: [PATCH RFC v8 51/56] KVM: SVM: Add module parameter to enable
 the SEV-SNP
Message-ID: <20230301124516.000048f5@intel.com>
In-Reply-To: <20230220183847.59159-52-michael.roth@amd.com>
References: <20230220183847.59159-1-michael.roth@amd.com>
        <20230220183847.59159-52-michael.roth@amd.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Precedence: bulk

On Mon, 20 Feb 2023 12:38:42 -0600
Michael Roth <michael.roth@amd.com> wrote:

> From: Brijesh Singh <brijesh.singh@amd.com>
> 
> Add a module parameter than can be used to enable or disable the SEV-SNP
> feature. Now that KVM contains the support for the SNP set the GHCB
> hypervisor feature flag to indicate that SNP is supported.
> 
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
> Signed-off-by: Michael Roth <michael.roth@amd.com>
> ---
>  arch/x86/kvm/svm/sev.c | 7 ++++---
>  arch/x86/kvm/svm/svm.h | 2 +-
>  2 files changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
> index bedec90d034f..70d5650d8d95 100644
> --- a/arch/x86/kvm/svm/sev.c
> +++ b/arch/x86/kvm/svm/sev.c
> @@ -55,14 +55,15 @@ module_param_named(sev, sev_enabled, bool, 0444);
>  /* enable/disable SEV-ES support */
>  static bool sev_es_enabled = true;
>  module_param_named(sev_es, sev_es_enabled, bool, 0444);
> +
> +/* enable/disable SEV-SNP support */
> +static bool sev_snp_enabled = true;
> +module_param_named(sev_snp, sev_snp_enabled, bool, 0444);
>  #else
>  #define sev_enabled false
>  #define sev_es_enabled false

Guess we also need #define sev_snp_enabled false.

>  #endif /* CONFIG_KVM_AMD_SEV */
>  
> -/* enable/disable SEV-SNP support */
> -static bool sev_snp_enabled;
> -
>  #define AP_RESET_HOLD_NONE		0
>  #define AP_RESET_HOLD_NAE_EVENT		1
>  #define AP_RESET_HOLD_MSR_PROTO		2
> diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
> index 857b674e68f0..221b38d3c845 100644
> --- a/arch/x86/kvm/svm/svm.h
> +++ b/arch/x86/kvm/svm/svm.h
> @@ -694,7 +694,7 @@ void avic_refresh_virtual_apic_mode(struct kvm_vcpu *vcpu);
>  #define GHCB_VERSION_MAX	2ULL
>  #define GHCB_VERSION_MIN	1ULL
>  
> -#define GHCB_HV_FT_SUPPORTED	0
> +#define GHCB_HV_FT_SUPPORTED	(GHCB_HV_FT_SNP | GHCB_HV_FT_SNP_AP_CREATION)

This is not related to the topic of this patch, should be merged into related
patches.

>  
>  extern unsigned int max_sev_asid;
>