diff --git a/hw/acpi/utils.c b/hw/acpi/utils.c
index f2d69a6d92..0c486ea29f 100644
--- a/hw/acpi/utils.c
+++ b/hw/acpi/utils.c
@@ -29,14 +29,19 @@
 MemoryRegion *acpi_add_rom_blob(FWCfgCallback update, void *opaque,
                                 GArray *blob, const char *name)
 {
-    uint64_t max_size = 0;
+    uint64_t max_size;
 
     /* Reserve RAM space for tables: add another order of magnitude. */
     if (!strcmp(name, ACPI_BUILD_TABLE_FILE)) {
         max_size = 0x200000;
     } else if (!strcmp(name, ACPI_BUILD_LOADER_FILE)) {
         max_size = 0x10000;
+    } else if (!strcmp(name, ACPI_BUILD_RSDP_FILE)) {
+        max_size = 0x1000;
+    } else {
+        g_assert_not_reached();
     }
+    g_assert(acpi_data_len(blob) <= max_size);
 
     return rom_add_blob(name, blob->data, acpi_data_len(blob), max_size, -1,
                         name, update, opaque, NULL, true);