[PATCH 03/62] x86/cpufeatures: Add SEV-ES CPU feature

From: Joerg Roedel
Date: Tue Feb 11 2020 - 08:53:13 EST


From: Tom Lendacky <thomas.lendacky@xxxxxxx>

Add CPU feature detection for Secure Encrypted Virtualization with
Encrypted State. This feature enhances SEV by also encrypting the
guest register state, making it in-accessible to the hypervisor.

Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/kernel/cpu/amd.c | 4 +++-
arch/x86/kernel/cpu/scattered.c | 1 +
3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index f3327cb56edf..26e4ee209f7b 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -285,6 +285,7 @@
#define X86_FEATURE_CQM_MBM_LOCAL (11*32+ 3) /* LLC Local MBM monitoring */
#define X86_FEATURE_FENCE_SWAPGS_USER (11*32+ 4) /* "" LFENCE in user entry SWAPGS path */
#define X86_FEATURE_FENCE_SWAPGS_KERNEL (11*32+ 5) /* "" LFENCE in kernel entry SWAPGS path */
+#define X86_FEATURE_SEV_ES (11*32+ 6) /* AMD Secure Encrypted Virtualization - Encrypted State */

/* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */
#define X86_FEATURE_AVX512_BF16 (12*32+ 5) /* AVX512 BFLOAT16 instructions */
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index ac83a0fef628..aad2223862ef 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -580,7 +580,7 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
* If BIOS has not enabled SME then don't advertise the
* SME feature (set in scattered.c).
* For SEV: If BIOS has not enabled SEV then don't advertise the
- * SEV feature (set in scattered.c).
+ * SEV and SEV_ES feature (set in scattered.c).
*
* In all cases, since support for SME and SEV requires long mode,
* don't advertise the feature under CONFIG_X86_32.
@@ -611,6 +611,8 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
setup_clear_cpu_cap(X86_FEATURE_SME);
clear_sev:
setup_clear_cpu_cap(X86_FEATURE_SEV);
+ setup_clear_cpu_cap(X86_FEATURE_SEV);
+ setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
}
}

diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 62b137c3c97a..30f354989cf1 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_MBA, CPUID_EBX, 6, 0x80000008, 0 },
{ X86_FEATURE_SME, CPUID_EAX, 0, 0x8000001f, 0 },
{ X86_FEATURE_SEV, CPUID_EAX, 1, 0x8000001f, 0 },
+ { X86_FEATURE_SEV_ES, CPUID_EAX, 3, 0x8000001f, 0 },
{ 0, 0, 0, 0, 0 }
};

--
2.17.1