From: Sean Christopherson <sean.j.christopher...@intel.com>

ENCLS and ENCLU are usable if and only if SGX_ENABLE is set and After
SGX is activated the IA32_SGXLEPUBKEYHASHn MSRs are writable if
SGX_LC_WR is set and the feature control is locked.

SGX related bits in IA32_FEATURE_CONTROL cannot be set before SGX is
activated by the pre-boot firmware. SGX activation is triggered by
setting bit 0 in the MSR 0x7a. Until SGX is activated, the LE hash MSRs
are writable to allow pre-boot firmware to lock down the LE root key
with a non-Intel value.

Signed-off-by: Sean Christopherson <sean.j.christopher...@intel.com>
Co-developed-by: Haim Cohen <haim.co...@intel.com>
Signed-off-by: Haim Cohen <haim.co...@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakki...@linux.intel.com>
---
 arch/x86/include/asm/msr-index.h | 8 ++++++++
 arch/x86/kernel/cpu/common.c     | 8 ++++----
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 4731f0cf97c5..44d7b68e7f52 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -486,6 +486,8 @@
 #define FEATURE_CONTROL_LOCKED                         (1<<0)
 #define FEATURE_CONTROL_VMXON_ENABLED_INSIDE_SMX       (1<<1)
 #define FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX      (1<<2)
+#define FEATURE_CONTROL_SGX_ENABLE                     (1<<18)
+#define FEATURE_CONTROL_SGX_LE_WR                      (1<<17)
 #define FEATURE_CONTROL_LMCE                           (1<<20)
 
 #define MSR_IA32_APICBASE              0x0000001b
@@ -552,6 +554,12 @@
 #define PACKAGE_THERM_INT_LOW_ENABLE           (1 << 1)
 #define PACKAGE_THERM_INT_PLN_ENABLE           (1 << 24)
 
+/* Intel SGX MSRs */
+#define MSR_IA32_SGXLEPUBKEYHASH0      0x0000008C
+#define MSR_IA32_SGXLEPUBKEYHASH1      0x0000008D
+#define MSR_IA32_SGXLEPUBKEYHASH2      0x0000008E
+#define MSR_IA32_SGXLEPUBKEYHASH3      0x0000008F
+
 /* Thermal Thresholds Support */
 #define THERM_INT_THRESHOLD0_ENABLE    (1 << 15)
 #define THERM_SHIFT_THRESHOLD0        8
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 211c76322ddf..282ceef992b0 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -52,6 +52,7 @@
 #include <asm/microcode_intel.h>
 #include <asm/intel-family.h>
 #include <asm/cpu_device_id.h>
+#include <asm/sgx_arch.h>
 
 #ifdef CONFIG_X86_LOCAL_APIC
 #include <asm/uv/uv.h>
@@ -866,10 +867,9 @@ void get_cpu_cap(struct cpuinfo_x86 *c)
                }
        }
 
-       /* Intel SGX features: level 0x00000012 */
-       if (c->cpuid_level >= 0x00000012) {
-               cpuid(0x00000012, &eax, &ebx, &ecx, &edx);
-
+       /* Intel SGX features */
+       if (c->cpuid_level >= SGX_CPUID) {
+               cpuid(SGX_CPUID,  &eax, &ebx, &ecx, &edx);
                c->x86_capability[CPUID_12_EAX] = eax;
        }
 
-- 
2.17.1

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