diff --git a/src/storage/storage_util.c b/src/storage/storage_util.c
index f71abbd729..8e43c7868d 100644
--- a/src/storage/storage_util.c
+++ b/src/storage/storage_util.c
@@ -3358,8 +3358,7 @@ storageBackendProbeTarget(virStorageSourcePtr target,
 
     if (!(meta = virStorageFileGetMetadataFromFD(target->path,
                                                  fd,
-                                                 VIR_STORAGE_FILE_AUTO,
-                                                 NULL)))
+                                                 VIR_STORAGE_FILE_AUTO)))
         return -1;
 
     if (meta->backingStoreRaw) {
diff --git a/src/util/virstoragefile.c b/src/util/virstoragefile.c
index 94805e8741..d5ac5970f1 100644
--- a/src/util/virstoragefile.c
+++ b/src/util/virstoragefile.c
@@ -1161,21 +1161,14 @@ virStorageFileGetMetadataFromBuf(const char *path,
 virStorageSourcePtr
 virStorageFileGetMetadataFromFD(const char *path,
                                 int fd,
-                                int format,
-                                int *backingFormat)
+                                int format)
 
 {
     ssize_t len = VIR_STORAGE_MAX_HEADER;
     struct stat sb;
-    int dummy;
     g_autofree char *buf = NULL;
     g_autoptr(virStorageSource) meta = NULL;
 
-    if (!backingFormat)
-        backingFormat = &dummy;
-
-    *backingFormat = VIR_STORAGE_FILE_NONE;
-
     if (fstat(fd, &sb) < 0) {
         virReportSystemError(errno,
                              _("cannot stat file '%s'"), path);
@@ -1206,9 +1199,6 @@ virStorageFileGetMetadataFromFD(const char *path,
     if (virStorageFileGetMetadataInternal(meta, buf, len) < 0)
         return NULL;
 
-    if (backingFormat)
-        *backingFormat = meta->backingStoreRawFormat;
-
     if (S_ISREG(sb.st_mode))
         meta->type = VIR_STORAGE_TYPE_FILE;
     else if (S_ISBLK(sb.st_mode))
diff --git a/src/util/virstoragefile.h b/src/util/virstoragefile.h
index 32f2c82147..5b995d54ab 100644
--- a/src/util/virstoragefile.h
+++ b/src/util/virstoragefile.h
@@ -381,8 +381,7 @@ int virStorageFileProbeFormat(const char *path, uid_t uid, gid_t gid);
 
 virStorageSourcePtr virStorageFileGetMetadataFromFD(const char *path,
                                                     int fd,
-                                                    int format,
-                                                    int *backingFormat);
+                                                    int format);
 virStorageSourcePtr virStorageFileGetMetadataFromBuf(const char *path,
                                                      char *buf,
                                                      size_t len,