cpuCompare: Fix comparison of two host CPUs

When a CPU to be compared with host CPU describes a host CPU instead of
a guest CPU, the result is incorrect. This is because instead of
treating additional features in host CPU description as required, they
were treated as if they were mentioned with all possible policies at the
same time.

src/cpu/cpu_x86.c

@@ -826,8 +826,7 @@ x86ModelFromCPU(const virCPUDefPtr cpu,
     struct x86_model *model = NULL;
     int i;
 
-    if (cpu->type == VIR_CPU_TYPE_HOST
-        || policy == VIR_CPU_FEATURE_REQUIRE) {
+    if (policy == VIR_CPU_FEATURE_REQUIRE) {
         if ((model = x86ModelFind(map, cpu->model)) == NULL) {
             virCPUReportError(VIR_ERR_INTERNAL_ERROR,
                     _("Unknown CPU model %s"), cpu->model);
@@ -839,6 +838,8 @@ x86ModelFromCPU(const virCPUDefPtr cpu,
     }
     else if (VIR_ALLOC(model) < 0)
         goto no_memory;
+    else if (cpu->type == VIR_CPU_TYPE_HOST)
+        return model;
 
     for (i = 0; i < cpu->nfeatures; i++) {
         const struct x86_feature *feature;
@@ -1181,7 +1182,7 @@ x86Compute(virCPUDefPtr host,
     }
 
     if (!(map = x86LoadMap()) ||
-        !(host_model = x86ModelFromCPU(host, map, 0)) ||
+        !(host_model = x86ModelFromCPU(host, map, VIR_CPU_FEATURE_REQUIRE)) ||
         !(cpu_force = x86ModelFromCPU(cpu, map, VIR_CPU_FEATURE_FORCE)) ||
         !(cpu_require = x86ModelFromCPU(cpu, map, VIR_CPU_FEATURE_REQUIRE)) ||
         !(cpu_optional = x86ModelFromCPU(cpu, map, VIR_CPU_FEATURE_OPTIONAL)) ||
@@ -1611,7 +1612,7 @@ x86Baseline(virCPUDefPtr *cpus,
     if (!(map = x86LoadMap()))
         goto error;
 
-    if (!(base_model = x86ModelFromCPU(cpus[0], map, 0)))
+    if (!(base_model = x86ModelFromCPU(cpus[0], map, VIR_CPU_FEATURE_REQUIRE)))
         goto error;
 
     if (VIR_ALLOC(cpu) < 0 ||
@@ -1630,7 +1631,7 @@ x86Baseline(virCPUDefPtr *cpus,
     for (i = 1; i < ncpus; i++) {
         const char *vn = NULL;
 
-        if (!(model = x86ModelFromCPU(cpus[i], map, 0)))
+        if (!(model = x86ModelFromCPU(cpus[i], map, VIR_CPU_FEATURE_REQUIRE)))
             goto error;
 
         if (cpus[i]->vendor && model->vendor &&
@@ -1710,7 +1711,7 @@ x86Update(virCPUDefPtr guest,
     union cpuData *data = NULL;
 
     if (!(map = x86LoadMap()) ||
-        !(host_model = x86ModelFromCPU(host, map, 0)))
+        !(host_model = x86ModelFromCPU(host, map, VIR_CPU_FEATURE_REQUIRE)))
         goto cleanup;
 
     for (i = 0; i < guest->nfeatures; i++) {