Re: [PATCH 2/3] MdeModulePkg/PartitionDxe: Remove the check for special MBR

["Ni, Ray" <ray.ni@intel.com>]

Zhichao,
Can you please just revert the fix you recently added?

> -----Original Message-----
> From: Gao, Zhichao <zhichao.gao@intel.com>
> Sent: Tuesday, August 11, 2020 2:43 PM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Wu, Hao A <hao.a.wu@intel.com>; Ni, Ray <ray.ni@intel.com>; Gary Lin
> <glin@suse.com>; Andrew Fish <afish@apple.com>
> Subject: [PATCH 2/3] MdeModulePkg/PartitionDxe: Remove the check for special MBR
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2823
> 
> Follow the spec definition, the ISO 9660 (and UDF) would be
> checked before the MBR. So it is not required to skip such
> MBR talbe that contian the entire block device.
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Hao A Wu <hao.a.wu@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Gary Lin <glin@suse.com>
> Cc: Andrew Fish <afish@apple.com>
> Signed-off-by: Zhichao Gao <zhichao.gao@intel.com>
> ---
>  .../Universal/Disk/PartitionDxe/Mbr.c         | 19 -------------------
>  1 file changed, 19 deletions(-)
> 
> diff --git a/MdeModulePkg/Universal/Disk/PartitionDxe/Mbr.c b/MdeModulePkg/Universal/Disk/PartitionDxe/Mbr.c
> index 3830af1ea7..822bf03e92 100644
> --- a/MdeModulePkg/Universal/Disk/PartitionDxe/Mbr.c
> +++ b/MdeModulePkg/Universal/Disk/PartitionDxe/Mbr.c
> @@ -55,25 +55,6 @@ PartitionValidMbr (
>      StartingLBA = UNPACK_UINT32 (Mbr->Partition[Index1].StartingLBA);
>      SizeInLBA   = UNPACK_UINT32 (Mbr->Partition[Index1].SizeInLBA);
> 
> -    //
> -    // If the MBR with partition entry covering the ENTIRE disk, i.e. start at LBA0
> -    // with whole disk size, we treat it as an invalid MBR partition.
> -    //
> -    if ((StartingLBA == 0) &&
> -        (SizeInLBA == (LastLba + 1))) {
> -      //
> -      // Refer to the http://manpages.ubuntu.com/manpages/bionic/man8/mkudffs.8.html
> -      // "WHOLE DISK VS PARTITION"
> -      // Some linux ISOs may put the MBR table in the first 512 bytes for compatibility reasons with Windows.
> -      // Linux  kernel  ignores MBR table if contains partition which starts at sector 0.
> -      // Skip it because we don't have the partition check for UDF(El Torito compatible).
> -      // It would continue to do the whole disk check in the UDF routine.
> -      //
> -      DEBUG ((DEBUG_INFO, "PartitionValidMbr: MBR table has partition entry covering the ENTIRE disk. Don't treat it as a
> valid MBR.\n"));
> -
> -      return FALSE;
> -    }
> -
>      if (Mbr->Partition[Index1].OSIndicator == 0x00 || SizeInLBA == 0) {
>        continue;
>      }
> --
> 2.21.0.windows.1