| Message ID | 20211210154332.11526-4-brijesh.singh@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add AMD Secure Nested Paging (SEV-SNP) Guest Support | expand |
On 2021-12-10 09:42:55 -0600, Brijesh Singh wrote: > The CC_ATTR_SEV_SNP can be used by the guest to query whether the SNP - > Secure Nested Paging feature is active. > > Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> > --- > + > + /** > + * @CC_ATTR_SEV_SNP: Guest SNP is active. > + * > + * The platform/OS is running as a guest/virtual machine and actively > + * using AMD SEV-SNP features. > + */ > + CC_ATTR_SEV_SNP = 0x100, Perhaps add a note on why this is being set to 0x100? With that... Reviewed-by: Venu Busireddy <venu.busireddy@oracle.com>
On Fri, Dec 10, 2021 at 09:42:55AM -0600, Brijesh Singh wrote: > diff --git a/include/linux/cc_platform.h b/include/linux/cc_platform.h > index a075b70b9a70..ef5e2209c9b8 100644 > --- a/include/linux/cc_platform.h > +++ b/include/linux/cc_platform.h > @@ -61,6 +61,14 @@ enum cc_attr { > * Examples include SEV-ES. > */ > CC_ATTR_GUEST_STATE_ENCRYPT, > + > + /** > + * @CC_ATTR_SEV_SNP: Guest SNP is active. > + * > + * The platform/OS is running as a guest/virtual machine and actively > + * using AMD SEV-SNP features. > + */ > + CC_ATTR_SEV_SNP = 0x100, I guess CC_ATTR_GUEST_SEV_SNP. The Intel is called CC_ATTR_GUEST_TDX so at least they all say it is a guest thing, this way.
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index 01e2650b9585..98a64b230447 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -481,8 +481,10 @@ #define MSR_AMD64_SEV 0xc0010131 #define MSR_AMD64_SEV_ENABLED_BIT 0 #define MSR_AMD64_SEV_ES_ENABLED_BIT 1 +#define MSR_AMD64_SEV_SNP_ENABLED_BIT 2 #define MSR_AMD64_SEV_ENABLED BIT_ULL(MSR_AMD64_SEV_ENABLED_BIT) #define MSR_AMD64_SEV_ES_ENABLED BIT_ULL(MSR_AMD64_SEV_ES_ENABLED_BIT) +#define MSR_AMD64_SEV_SNP_ENABLED BIT_ULL(MSR_AMD64_SEV_SNP_ENABLED_BIT) #define MSR_AMD64_VIRT_SPEC_CTRL 0xc001011f diff --git a/arch/x86/kernel/cc_platform.c b/arch/x86/kernel/cc_platform.c index 03bb2f343ddb..e05310f5ec2f 100644 --- a/arch/x86/kernel/cc_platform.c +++ b/arch/x86/kernel/cc_platform.c @@ -50,6 +50,8 @@ static bool amd_cc_platform_has(enum cc_attr attr) case CC_ATTR_GUEST_STATE_ENCRYPT: return sev_status & MSR_AMD64_SEV_ES_ENABLED; + case CC_ATTR_SEV_SNP: + return sev_status & MSR_AMD64_SEV_SNP_ENABLED; default: return false; } diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 35487305d8af..3ba801ff6afc 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -487,6 +487,10 @@ static void print_mem_encrypt_feature_info(void) if (cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)) pr_cont(" SEV-ES"); + /* Secure Nested Paging */ + if (cc_platform_has(CC_ATTR_SEV_SNP)) + pr_cont(" SEV-SNP"); + pr_cont("\n"); } diff --git a/include/linux/cc_platform.h b/include/linux/cc_platform.h index a075b70b9a70..ef5e2209c9b8 100644 --- a/include/linux/cc_platform.h +++ b/include/linux/cc_platform.h @@ -61,6 +61,14 @@ enum cc_attr { * Examples include SEV-ES. */ CC_ATTR_GUEST_STATE_ENCRYPT, + + /** + * @CC_ATTR_SEV_SNP: Guest SNP is active. + * + * The platform/OS is running as a guest/virtual machine and actively + * using AMD SEV-SNP features. + */ + CC_ATTR_SEV_SNP = 0x100, }; #ifdef CONFIG_ARCH_HAS_CC_PLATFORM
The CC_ATTR_SEV_SNP can be used by the guest to query whether the SNP - Secure Nested Paging feature is active. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> --- arch/x86/include/asm/msr-index.h | 2 ++ arch/x86/kernel/cc_platform.c | 2 ++ arch/x86/mm/mem_encrypt.c | 4 ++++ include/linux/cc_platform.h | 8 ++++++++ 4 files changed, 16 insertions(+)