diff --git a/GRUB2/MOD_SRC/grub-2.04/grub-core/commands/hashsum.c b/GRUB2/MOD_SRC/grub-2.04/grub-core/commands/hashsum.c
index 1b0bfda9..7bca70e4 100644
--- a/GRUB2/MOD_SRC/grub-2.04/grub-core/commands/hashsum.c
+++ b/GRUB2/MOD_SRC/grub-2.04/grub-core/commands/hashsum.c
@@ -69,7 +69,7 @@ hash_file (grub_file_t file, const gcry_md_spec_t *hash, void *result)
   grub_uint64_t total = 0;
   void *context;
   grub_uint8_t *readbuf;
-#define BUF_SIZE 4096
+#define BUF_SIZE 1024 * 1024
   readbuf = grub_malloc (BUF_SIZE);
   if (!readbuf)
     return grub_errno;