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target/i386/cpu: Remove unnecessary SGX feature words checks

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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>
Link: https://lore.kernel.org/r/20240730045544.2516284-2-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Zhao Liu 2024-07-30 12:55:41 +08:00 committed by Paolo Bonzini
parent 39635ccd0b
commit eee194dd71
1 changed files with 1 additions and 15 deletions
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16
target/i386/cpu.c
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@ -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) {