[U-Boot] [PATCH v2] part_efi: fix protective mbr struct allocation

[Hector Palacios]

The calloc() call was allocating space for the sizeof the struct
pointer rather than for the struct contents.
Besides, since this buffer is passed to mmc for writing and some
platforms may use cache, the legacy_mbr struct should be cache-aligned.

Signed-off-by: Hector Palacios <hector.palacios at digi.com>
---

Notes:
    Changes since V1:
            - Cache-align declaration of p_mbr pointer
            - Use *p_mbr in sizeof() to match kernel CodingStyle

 disk/part_efi.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/disk/part_efi.c b/disk/part_efi.c
index 5dfaf490c89a..42936e04fb67 100644
--- a/disk/part_efi.c
+++ b/disk/part_efi.c
@@ -229,10 +229,10 @@ int test_part_efi(block_dev_desc_t * dev_desc)
  */
 static int set_protective_mbr(block_dev_desc_t *dev_desc)
 {
-	legacy_mbr *p_mbr;
-
 	/* Setup the Protective MBR */
-	p_mbr = calloc(1, sizeof(p_mbr));
+	ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, p_mbr, 1);
+	memset(p_mbr, 0, sizeof(*p_mbr));
+
 	if (p_mbr == NULL) {
 		printf("%s: calloc failed!\n", __func__);
 		return -1;
@@ -247,11 +247,9 @@ static int set_protective_mbr(block_dev_desc_t *dev_desc)
 	if (dev_desc->block_write(dev_desc->dev, 0, 1, p_mbr) != 1) {
 		printf("** Can't write to device %d **\n",
 			dev_desc->dev);
-		free(p_mbr);
 		return -1;
 	}
 
-	free(p_mbr);
 	return 0;
 }