@@ -145,6 +145,9 @@ void sev_es_shutdown_ghcb(void)
if (!boot_ghcb)
return;
+ if (!sev_es_check_cpu_features())
+ error("SEV-ES CPU Features missing.");
+
/*
* GHCB Page must be flushed from the cache and mapped encrypted again.
* Otherwise the running kernel will see strange cache effects when
@@ -9,6 +9,21 @@
* and is included directly into both code-bases.
*/
+#ifndef __BOOT_COMPRESSED
+#define error(v) pr_err(v)
+#define has_cpuflag(f) boot_cpu_has(f)
+#endif
+
+static bool __init sev_es_check_cpu_features(void)
+{
+ if (!has_cpuflag(X86_FEATURE_RDRAND)) {
+ error("RDRAND instruction not supported - no trusted source of randomness available\n");
+ return false;
+ }
+
+ return true;
+}
+
static void sev_es_terminate(unsigned int reason)
{
u64 val = GHCB_SEV_TERMINATE;
@@ -682,6 +682,9 @@ void __init sev_es_init_vc_handling(void)
if (!sev_es_active())
return;
+ if (!sev_es_check_cpu_features())
+ panic("SEV-ES CPU Features missing");
+
/* Initialize per-cpu GHCB pages */
for_each_possible_cpu(cpu) {
sev_es_alloc_runtime_data(cpu);