diff --git a/mtdutils/mounts.c b/mtdutils/mounts.c
index 2ab3ff6..c90fc8a 100644
--- a/mtdutils/mounts.c
+++ b/mtdutils/mounts.c
@@ -212,3 +212,11 @@
     }
     return ret;
 }
+
+int
+remount_read_only(const MountedVolume* volume)
+{
+    return mount(volume->device, volume->mount_point, volume->filesystem,
+                 MS_NOATIME | MS_NODEV | MS_NODIRATIME |
+                 MS_RDONLY | MS_REMOUNT, 0);
+}
diff --git a/mtdutils/mounts.h b/mtdutils/mounts.h
index 2e2765a..30b2927 100644
--- a/mtdutils/mounts.h
+++ b/mtdutils/mounts.h
@@ -28,4 +28,6 @@
 
 int unmount_mounted_volume(const MountedVolume *volume);
 
+int remount_read_only(const MountedVolume* volume);
+
 #endif  // MTDUTILS_MOUNTS_H_
diff --git a/mtdutils/mtdutils.c b/mtdutils/mtdutils.c
index d16f44e..48d5ea9 100644
--- a/mtdutils/mtdutils.c
+++ b/mtdutils/mtdutils.c
@@ -455,7 +455,7 @@
             if (retry > 0) {
                 fprintf(stderr, "mtd: wrote block after %d retries\n", retry);
             }
-            fprintf(stderr, "mtd: successfully wrote block at %x\n", pos);
+            fprintf(stderr, "mtd: successfully wrote block at %llx\n", pos);
             return 0;  // Success!
         }