[syslinux:master] isohdpfx: update to the new !GPT protocol

[syslinux-bot for H. Peter Anvin]

Commit-ID:  7ccf85b2a873bba3f363ad2df05457dd160c3f6d
Gitweb:     http://syslinux.zytor.com/commit/7ccf85b2a873bba3f363ad2df05457dd160c3f6d
Author:     H. Peter Anvin <hpa at zytor.com>
AuthorDate: Sun, 27 Jun 2010 11:43:49 -0700
Committer:  H. Peter Anvin <hpa at zytor.com>
CommitDate: Sun, 27 Jun 2010 11:43:49 -0700

isohdpfx: update to the new !GPT protocol

Update the check for !GPT to match the updated protocol (with length).

Signed-off-by: H. Peter Anvin <hpa at zytor.com>


---
 mbr/isohdpfx.S |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/mbr/isohdpfx.S b/mbr/isohdpfx.S
index 801115c..0bf807e 100644
--- a/mbr/isohdpfx.S
+++ b/mbr/isohdpfx.S
@@ -81,14 +81,16 @@ _start:
 	jz	1f
 	testb	$0x7f, (%si)		/* Invalid active flag field? */
 	jnz	1f
+	cmpb	%cl, 4(%si)		/* Partition type zero == invalid? */
+	je	1f
 	cmpl	$0x58504721, %eax	/* !GPT signature in EAX? */
 	jne	2f
-	cmpb	$0xee, 4(%si)		/* EFI partition type? */
+	cmpb	$0xed, 4(%si)		/* EFI partition type? */
 	jne	2f
 	
 	/* We have GPT partition information */
-	movl	(32+16)(%si), %ecx
-	movl	(36+16)(%si), %ebx
+	movl	(32+20)(%si), %ecx
+	movl	(36+20)(%si), %ebx
 	jmp	1f
 
 	/* We have non-GPT partition information */