On 2/20/23 10:38 AM, Michael Roth wrote: > From: Brijesh Singh <brijesh.singh@xxxxxxx> > > Add CPU feature detection for Secure Encrypted Virtualization with > Secure Nested Paging. This feature adds a strong memory integrity > protection to help prevent malicious hypervisor-based attacks like > data replay, memory re-mapping, and more. > > Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx> > Signed-off-by: Jarkko Sakkinen <jarkko@xxxxxxxxxxx> > Signed-off-by: Ashish Kalra <Ashish.Kalra@xxxxxxx> Too many signed-off-by's. Are you missing Co-developed-by? > Signed-off-by: Michael Roth <michael.roth@xxxxxxx> > --- > arch/x86/include/asm/cpufeatures.h | 1 + > arch/x86/kernel/cpu/amd.c | 5 +++-- > tools/arch/x86/include/asm/cpufeatures.h | 1 + > 3 files changed, 5 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h > index 1419c4e04d45..480b4eaef310 100644 > --- a/arch/x86/include/asm/cpufeatures.h > +++ b/arch/x86/include/asm/cpufeatures.h > @@ -420,6 +420,7 @@ > #define X86_FEATURE_SEV (19*32+ 1) /* AMD Secure Encrypted Virtualization */ > #define X86_FEATURE_VM_PAGE_FLUSH (19*32+ 2) /* "" VM Page Flush MSR is supported */ > #define X86_FEATURE_SEV_ES (19*32+ 3) /* AMD Secure Encrypted Virtualization - Encrypted State */ > +#define X86_FEATURE_SEV_SNP (19*32+ 4) /* AMD Secure Encrypted Virtualization - Secure Nested Paging */ > #define X86_FEATURE_V_TSC_AUX (19*32+ 9) /* "" Virtual TSC_AUX */ > #define X86_FEATURE_SME_COHERENT (19*32+10) /* "" AMD hardware-enforced cache coherency */ > > diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c > index 860b60273df3..c7884198ad5b 100644 > --- a/arch/x86/kernel/cpu/amd.c > +++ b/arch/x86/kernel/cpu/amd.c > @@ -558,8 +558,8 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c) > * SME feature (set in scattered.c). > * If the kernel has not enabled SME via any means then > * don't advertise the SME feature. > - * For SEV: If BIOS has not enabled SEV then don't advertise the > - * SEV and SEV_ES feature (set in scattered.c). Did you remove the related scattered.c code mentioned above in a different patch? > + * For SEV: If BIOS has not enabled SEV then don't advertise SEV and > + * any additional functionality based on it. > * > * In all cases, since support for SME and SEV requires long mode, > * don't advertise the feature under CONFIG_X86_32. > @@ -594,6 +594,7 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c) > clear_sev: > setup_clear_cpu_cap(X86_FEATURE_SEV); > setup_clear_cpu_cap(X86_FEATURE_SEV_ES); > + setup_clear_cpu_cap(X86_FEATURE_SEV_SNP); > } > } > > diff --git a/tools/arch/x86/include/asm/cpufeatures.h b/tools/arch/x86/include/asm/cpufeatures.h > index b71f4f2ecdd5..e81606fcd2ab 100644 > --- a/tools/arch/x86/include/asm/cpufeatures.h > +++ b/tools/arch/x86/include/asm/cpufeatures.h > @@ -417,6 +417,7 @@ > #define X86_FEATURE_SEV (19*32+ 1) /* AMD Secure Encrypted Virtualization */ > #define X86_FEATURE_VM_PAGE_FLUSH (19*32+ 2) /* "" VM Page Flush MSR is supported */ > #define X86_FEATURE_SEV_ES (19*32+ 3) /* AMD Secure Encrypted Virtualization - Encrypted State */ > +#define X86_FEATURE_SEV_SNP (19*32+ 4) /* AMD Secure Encrypted Virtualization - Secure Nested Paging */ > #define X86_FEATURE_V_TSC_AUX (19*32+ 9) /* "" Virtual TSC_AUX */ > #define X86_FEATURE_SME_COHERENT (19*32+10) /* "" AMD hardware-enforced cache coherency */ > -- Sathyanarayanan Kuppuswamy Linux Kernel Developer