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[1/4] target/i386/cpu: Remove unnecessary SGX feature words checks

Message ID 20240730045544.2516284-2-zhao1.liu@intel.com (mailing list archive)
State New, archived
Headers show
Series i386: Clean up SGX for microvm, completely | expand

Commit Message

Zhao Liu July 30, 2024, 4:55 a.m. UTC 
CPUID.0x7.0.ebx and CPUID.0x7.0.ecx leaves have been expressed as the
feature word lists, and the Host capability support has been checked
in x86_cpu_filter_features().

Therefore, such checks on SGX feature "words" are redundant, and
the follow-up adjustments to those feature "words" will not actually
take effect.

Remove unnecessary SGX feature words related checks.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
---
 target/i386/cpu.c | 16 +---------------
 1 file changed, 1 insertion(+), 15 deletions(-)
diff mbox series

Patch

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 4688d140c2d9..2b3642c9b13c 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -6537,8 +6537,6 @@  void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
     case 7:
         /* Structured Extended Feature Flags Enumeration Leaf */
         if (count == 0) {
-            uint32_t eax_0_unused, ebx_0, ecx_0, edx_0_unused;
-
             /* Maximum ECX value for sub-leaves */
             *eax = env->cpuid_level_func7;
             *ebx = env->features[FEAT_7_0_EBX]; /* Feature flags */
@@ -6548,20 +6546,8 @@  void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
             }
             *edx = env->features[FEAT_7_0_EDX]; /* Feature flags */
 
-            /*
-             * SGX cannot be emulated in software.  If hardware does not
-             * support enabling SGX and/or SGX flexible launch control,
-             * then we need to update the VM's CPUID values accordingly.
-             */
-            x86_cpu_get_supported_cpuid(0x7, 0,
-                                        &eax_0_unused, &ebx_0,
-                                        &ecx_0, &edx_0_unused);
-            if ((*ebx & CPUID_7_0_EBX_SGX) && !(ebx_0 & CPUID_7_0_EBX_SGX)) {
-                *ebx &= ~CPUID_7_0_EBX_SGX;
-            }
-
             if ((*ecx & CPUID_7_0_ECX_SGX_LC)
-                    && (!(*ebx & CPUID_7_0_EBX_SGX) || !(ecx_0 & CPUID_7_0_ECX_SGX_LC))) {
+                    && (!(*ebx & CPUID_7_0_EBX_SGX))) {
                 *ecx &= ~CPUID_7_0_ECX_SGX_LC;
             }
         } else if (count == 1) {