[PULL,37/38] i386/cpu: Set up CPUID_HT in x86_cpu_expand_features() instead of cpu_x86_cpuid()

Commit Message

Paolo Bonzini Jan. 10, 2025, 6:46 p.m. UTC

From: Xiaoyao Li <[e-mail]>

Currently CPUID_HT is evaluated in cpu_x86_cpuid() each time. It's not a
correct usage of how feature bit is maintained and evaluated. The
expected practice is that features are tracked in env->features[] and
cpu_x86_cpuid() should be the consumer of env->features[].

Track CPUID_HT in env->features[FEAT_1_EDX] instead and evaluate it in
cpu's realizefn().

Signed-off-by: Xiaoyao Li <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Paolo Bonzini <[e-mail]>
---
 target/i386/cpu.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Patch

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 3f9475b4856..3f0821c15f2 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -6538,7 +6538,6 @@  void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
         *edx = env->features[FEAT_1_EDX];
         if (threads_per_pkg > 1) {
             *ebx |= threads_per_pkg << 16;
-            *edx |= CPUID_HT;
         }
         if (!cpu->enable_pmu) {
             *ecx &= ~CPUID_EXT_PDCM;
@@ -7529,6 +7528,10 @@  void x86_cpu_expand_features(X86CPU *cpu, Error **errp)
         }
     }
 
+    if (x86_threads_per_pkg(&env->topo_info) > 1) {
+        env->features[FEAT_1_EDX] |= CPUID_HT;
+    }
+
     for (i = 0; i < ARRAY_SIZE(feature_dependencies); i++) {
         FeatureDep *d = &feature_dependencies[i];
         if (!(env->features[d->from.index] & d->from.mask)) {