diff --git a/hw/core/register.c b/hw/core/register.c
index da38ef3a54..900294b9c4 100644
--- a/hw/core/register.c
+++ b/hw/core/register.c
@@ -195,8 +195,8 @@ void register_write_memory(void *opaque, hwaddr addr,
     }
 
     if (!reg) {
-        qemu_log_mask(LOG_GUEST_ERROR, "Write to unimplemented register at " \
-                      "address: %#" PRIx64 "\n", addr);
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: write to unimplemented register " \
+                      "at address: %#" PRIx64 "\n", reg_array->prefix, addr);
         return;
     }
 
@@ -224,8 +224,8 @@ uint64_t register_read_memory(void *opaque, hwaddr addr,
     }
 
     if (!reg) {
-        qemu_log_mask(LOG_GUEST_ERROR, "Read to unimplemented register at " \
-                      "address: %#" PRIx64 "\n", addr);
+        qemu_log_mask(LOG_GUEST_ERROR, "%s:  read to unimplemented register " \
+                      "at address: %#" PRIx64 "\n", reg_array->prefix, addr);
         return 0;
     }