Index: sys/kern/vfs_mount.c
===================================================================
--- sys/kern/vfs_mount.c
+++ sys/kern/vfs_mount.c
@@ -969,8 +969,10 @@
 		if (error1 != 0) {
 			error = error1;
 			rootvp = vfs_cache_root_clear(mp);
-			if (rootvp != NULL)
+			if (rootvp != NULL) {
+				vn_seqc_write_end(rootvp);
 				vrele(rootvp);
+			}
 			if ((error1 = VFS_UNMOUNT(mp, 0)) != 0)
 				printf("VFS_UNMOUNT returned %d\n", error1);
 		}