1 files changed, 48 insertions, 0 deletions
diff --git a/hw/core/machine-smp.c b/hw/core/machine-smp.c
index ebb7a134a7..640b2114b4 100644
--- a/hw/core/machine-smp.c
+++ b/hw/core/machine-smp.c
@@ -348,3 +348,51 @@ void machine_set_cache_topo_level(MachineState *ms, CacheLevelAndType cache,
 {
     ms->smp_cache.props[cache].topology = level;
 }
+
+/*
+ * When both cache1 and cache2 are configured with specific topology levels
+ * (not default level), is cache1's topology level higher than cache2?
+ */
+static bool smp_cache_topo_cmp(const SmpCache *smp_cache,
+                               CacheLevelAndType cache1,
+                               CacheLevelAndType cache2)
+{
+    /*
+     * Before comparing, the "default" topology level should be replaced
+     * with the specific level.
+     */
+    assert(smp_cache->props[cache1].topology != CPU_TOPOLOGY_LEVEL_DEFAULT);
+
+    return smp_cache->props[cache1].topology > smp_cache->props[cache2].topology;
+}
+
+/*
+ * Currently, we have no way to expose the arch-specific default cache model
+ * because the cache model is sometimes related to the CPU model (e.g., i386).
+ *
+ * We can only check the correctness of the cache topology after the arch loads
+ * the user-configured cache model from MachineState and consumes the special
+ * "default" level by replacing it with the specific level.
+ */
+bool machine_check_smp_cache(const MachineState *ms, Error **errp)
+{
+    if (smp_cache_topo_cmp(&ms->smp_cache, CACHE_LEVEL_AND_TYPE_L1D,
+                           CACHE_LEVEL_AND_TYPE_L2) ||
+        smp_cache_topo_cmp(&ms->smp_cache, CACHE_LEVEL_AND_TYPE_L1I,
+                           CACHE_LEVEL_AND_TYPE_L2)) {
+        error_setg(errp,
+                   "Invalid smp cache topology. "
+                   "L2 cache topology level shouldn't be lower than L1 cache");
+        return false;
+    }
+
+    if (smp_cache_topo_cmp(&ms->smp_cache, CACHE_LEVEL_AND_TYPE_L2,
+                           CACHE_LEVEL_AND_TYPE_L3)) {
+        error_setg(errp,
+                   "Invalid smp cache topology. "
+                   "L3 cache topology level shouldn't be lower than L2 cache");
+        return false;
+    }
+
+    return true;
+}