Hi,
I *think* this is how it should be done but I might be forgetting something.
It seems to work in my testing here.
Babu, double-check me pls.
Thx.
---
Add CPUID leaf 0x8000_0021.ECX support and add the TSA CPUID flags.
Signed-off-by: Borislav Petkov (AMD) <b...@alien8.de>
---
target/i386/cpu.c | 20 +++++++++++++++++++-
target/i386/cpu.h | 3 +++
2 files changed, 22 insertions(+), 1 deletion(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 0d35e95430fe..b889de61ed9d 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1274,7 +1274,7 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
.type = CPUID_FEATURE_WORD,
.feat_names = {
"no-nested-data-bp", "fs-gs-base-ns", "lfence-always-serializing",
NULL,
- NULL, NULL, "null-sel-clr-base", NULL,
+ NULL, "verw-clear", "null-sel-clr-base", NULL,
"auto-ibrs", NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
@@ -1308,6 +1308,22 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
.tcg_features = 0,
.unmigratable_flags = 0,
},
+ [FEAT_8000_0021_ECX] = {
+ .type = CPUID_FEATURE_WORD,
+ .feat_names = {
+ NULL, "tsa-sq-no", "tsa-l1-no", NULL,
+ NULL, NULL, NULL, NULL,
+ NULL, NULL, NULL, NULL,
+ NULL, NULL, NULL, NULL,
+ NULL, NULL, NULL, NULL,
+ NULL, NULL, NULL, NULL,
+ NULL, NULL, NULL, NULL,
+ NULL, NULL, NULL, NULL,
+ },
+ .cpuid = { .eax = 0x80000021, .reg = R_ECX, },
+ .tcg_features = 0,
+ .unmigratable_flags = 0,
+ },
[FEAT_XSAVE] = {
.type = CPUID_FEATURE_WORD,
.feat_names = {
@@ -5835,6 +5851,7 @@ static const X86CPUDefinition builtin_x86_defs[] = {
.features[FEAT_8000_0021_EAX] =
CPUID_8000_0021_EAX_NO_NESTED_DATA_BP |
CPUID_8000_0021_EAX_LFENCE_ALWAYS_SERIALIZING |
+ CPUID_8000_0021_EAX_VERW_CLEAR |
CPUID_8000_0021_EAX_NULL_SEL_CLR_BASE |
CPUID_8000_0021_EAX_AUTO_IBRS,
.features[FEAT_7_0_EBX] =
@@ -7934,6 +7951,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
uint32_t count,
*eax = *ebx = *ecx = *edx = 0;
*eax = env->features[FEAT_8000_0021_EAX];
*ebx = env->features[FEAT_8000_0021_EBX];
+ *ecx = env->features[FEAT_8000_0021_ECX];
break;
default:
/* reserved values: zero */
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 51e10139dfdf..8b2703f41b73 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -641,6 +641,7 @@ typedef enum FeatureWord {
FEAT_8000_0008_EBX, /* CPUID[8000_0008].EBX */
FEAT_8000_0021_EAX, /* CPUID[8000_0021].EAX */
FEAT_8000_0021_EBX, /* CPUID[8000_0021].EBX */
+ FEAT_8000_0021_ECX, /* CPUID[8000_0021].ECX */
FEAT_8000_0022_EAX, /* CPUID[8000_0022].EAX */
FEAT_C000_0001_EDX, /* CPUID[C000_0001].EDX */
FEAT_KVM, /* CPUID[4000_0001].EAX (KVM_CPUID_FEATURES) */
@@ -1101,6 +1102,8 @@ uint64_t x86_cpu_get_supported_feature_word(X86CPU *cpu,
FeatureWord w);
#define CPUID_8000_0021_EAX_FS_GS_BASE_NS (1U << 1)
/* LFENCE is always serializing */
#define CPUID_8000_0021_EAX_LFENCE_ALWAYS_SERIALIZING (1U << 2)
+/* Memory form of VERW mitigates TSA */
+#define CPUID_8000_0021_EAX_VERW_CLEAR (1U << 5)
/* Null Selector Clears Base */
#define CPUID_8000_0021_EAX_NULL_SEL_CLR_BASE (1U << 6)
/* Automatic IBRS */
--
2.43.0
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
