Some ChromeOS devices (atleast veyron speedy) have the first 8MiB of the eMMC write protected and equipped with a dummy 'IGNOREME' GPT header - instead of spewing error messages about it, just silently try the backup GPT.
Note: this does not touch the gpt cmd writing/verifying functions, those will still complain.
Signed-off-by: Urja Rannikko urjaman@gmail.com --- disk/part_efi.c | 28 +++++++++++++++++++++------- include/part_efi.h | 2 ++ 2 files changed, 23 insertions(+), 7 deletions(-)
diff --git a/disk/part_efi.c b/disk/part_efi.c index 5f935da4c2..83ba7db665 100644 --- a/disk/part_efi.c +++ b/disk/part_efi.c @@ -893,7 +893,7 @@ static int is_pmbr_valid(legacy_mbr * mbr) * gpt is a GPT header ptr, filled on return. * ptes is a PTEs ptr, filled on return. * - * Description: returns 1 if valid, 0 on error. + * Description: returns 1 if valid, 0 on error, 2 if ignored header * If valid, returns pointers to PTEs. */ static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba, @@ -919,6 +919,12 @@ static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba, return 0; }
+ /* Invalid but nothing to yell about. */ + if (le64_to_cpu(pgpt_head->signature) == GPT_HEADER_CHROMEOS_IGNORE) { + debug("ChromeOS 'IGNOREME' GPT header found and ignored\n"); + return 2; + } + if (validate_gpt_header(pgpt_head, (lbaint_t)lba, dev_desc->lba)) return 0;
@@ -962,16 +968,24 @@ static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba, static int find_valid_gpt(struct blk_desc *dev_desc, gpt_header *gpt_head, gpt_entry **pgpt_pte) { - if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA, - gpt_head, pgpt_pte) != 1) { - printf("%s: *** ERROR: Invalid GPT ***\n", __func__); - if (is_gpt_valid(dev_desc, (dev_desc->lba - 1), - gpt_head, pgpt_pte) != 1) { + int r; + + r = is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA, gpt_head, + pgpt_pte); + + if (r != 1) { + if (r != 2) + printf("%s: *** ERROR: Invalid GPT ***\n", __func__); + + if (is_gpt_valid(dev_desc, (dev_desc->lba - 1), gpt_head, + pgpt_pte) != 1) { printf("%s: *** ERROR: Invalid Backup GPT ***\n", __func__); return 0; } - printf("%s: *** Using Backup GPT ***\n", __func__); + if (r != 2) + printf("%s: *** Using Backup GPT ***\n", + __func__); } return 1; } diff --git a/include/part_efi.h b/include/part_efi.h index 7170b61c95..eb5797af74 100644 --- a/include/part_efi.h +++ b/include/part_efi.h @@ -25,6 +25,8 @@ #define EFI_PMBR_OSTYPE_EFI_GPT 0xEE
#define GPT_HEADER_SIGNATURE_UBOOT 0x5452415020494645ULL +#define GPT_HEADER_CHROMEOS_IGNORE 0x454d45524f4e4749ULL // 'IGNOREME' + #define GPT_HEADER_REVISION_V1 0x00010000 #define GPT_PRIMARY_PARTITION_TABLE_LBA 1ULL #define GPT_ENTRY_NUMBERS CONFIG_EFI_PARTITION_ENTRIES_NUMBERS