On Mon, 2025-05-19 at 10:24 +0300, Elena Reshetova wrote:
> Add a flag indicating whenever ENCLS[EUPDATESVN] SGX instruction
> is supported. This will be used by SGX driver to perform CPU
> SVN updates.
>
> Signed-off-by: Elena Reshetova <elena.reshet...@intel.com>
> ---
> arch/x86/include/asm/cpufeatures.h | 1 +
> arch/x86/kernel/cpu/scattered.c | 1 +
> tools/arch/x86/include/asm/cpufeatures.h | 1 +
> 3 files changed, 3 insertions(+)
>
> diff --git a/arch/x86/include/asm/cpufeatures.h
> b/arch/x86/include/asm/cpufeatures.h
> index 6c2c152d8a67..ed0c0fa5822a 100644
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@ -481,6 +481,7 @@
> #define X86_FEATURE_AMD_HETEROGENEOUS_CORES (21*32 + 6) /* Heterogeneous
> Core Topology */
> #define X86_FEATURE_AMD_WORKLOAD_CLASS (21*32 + 7) /* Workload
> Classification */
> #define X86_FEATURE_PREFER_YMM (21*32 + 8) /* Avoid ZMM
> registers due to downclocking */
> +#define X86_FEATURE_SGX_EUPDATESVN (21*32 + 9) /* Support for
> ENCLS[EUPDATESVN] instruction */
>
> /*
> * BUG word(s)
> diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
> index 16f3ca30626a..a7e1fcedca3c 100644
> --- a/arch/x86/kernel/cpu/scattered.c
> +++ b/arch/x86/kernel/cpu/scattered.c
> @@ -41,6 +41,7 @@ static const struct cpuid_bit cpuid_bits[] = {
> { X86_FEATURE_PER_THREAD_MBA, CPUID_ECX, 0, 0x00000010, 3 },
> { X86_FEATURE_SGX1, CPUID_EAX, 0, 0x00000012, 0 },
> { X86_FEATURE_SGX2, CPUID_EAX, 1, 0x00000012, 0 },
> + { X86_FEATURE_SGX_EUPDATESVN, CPUID_EAX, 10, 0x00000012, 0 },
> { X86_FEATURE_SGX_EDECCSSA, CPUID_EAX, 11, 0x00000012, 0 },
> { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 },
> { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 },
> diff --git a/tools/arch/x86/include/asm/cpufeatures.h
> b/tools/arch/x86/include/asm/cpufeatures.h
> index 6c2c152d8a67..ed0c0fa5822a 100644
> --- a/tools/arch/x86/include/asm/cpufeatures.h
> +++ b/tools/arch/x86/include/asm/cpufeatures.h
> @@ -481,6 +481,7 @@
> #define X86_FEATURE_AMD_HETEROGENEOUS_CORES (21*32 + 6) /* Heterogeneous
> Core Topology */
> #define X86_FEATURE_AMD_WORKLOAD_CLASS (21*32 + 7) /* Workload
> Classification */
> #define X86_FEATURE_PREFER_YMM (21*32 + 8) /* Avoid ZMM
> registers due to downclocking */
> +#define X86_FEATURE_SGX_EUPDATESVN (21*32 + 9) /* Support for
> ENCLS[EUPDATESVN] instruction */
>
>
Additionally, the new feature bit should be added to the CPUID dependency table:
--- a/arch/x86/kernel/cpu/cpuid-deps.c
+++ b/arch/x86/kernel/cpu/cpuid-deps.c
@@ -78,6 +78,7 @@ static const struct cpuid_dep cpuid_deps[] = {
{ X86_FEATURE_SGX_LC, X86_FEATURE_SGX },
{ X86_FEATURE_SGX1, X86_FEATURE_SGX },
{ X86_FEATURE_SGX2, X86_FEATURE_SGX1 },
+ { X86_FEATURE_SGX_EUPDATESVN, X86_FEATURE_SGX1 },
{ X86_FEATURE_SGX_EDECCSSA, X86_FEATURE_SGX1 },
{ X86_FEATURE_XFD, X86_FEATURE_XSAVES },
{ X86_FEATURE_XFD, X86_FEATURE_XGETBV1 },
