[GIT PULL] Correct the SMAP check in the e820 probe

From: H. Peter Anvin
Date: Fri Sep 28 2007 - 04:57:22 EST

Hi Linus,

Please pull:

git://git.kernel.org/pub/scm/linux/kernel/git/hpa/linux-2.6-x86setup.git for-linus

H. Peter Anvin (1):
[x86 setup] Correct the SMAP check for INT 0x15, AX=0xe820

arch/i386/boot/memory.c | 5 ++---
1 files changed, 2 insertions(+), 3 deletions(-)

[Log messages and full diffs follow]

commit 24b4ac15fe9ea5772630e0c58d9b6243a6c68385
Author: H. Peter Anvin <hpa@xxxxxxxxx>
Date: Thu Sep 27 17:17:12 2007 -0700

[x86 setup] Correct the SMAP check for INT 0x15, AX=0xe820

The e820 probe code was checking %edx, not %eax, for the SMAP
signature on return. This worked on *almost* all systems, since %edx
still contained SMAP from the call on entry, but on a handful of
systems it failed -- plus, we would have missed real mismatches.

Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxx>

diff --git a/arch/i386/boot/memory.c b/arch/i386/boot/memory.c
index bccaa1c..2f37568 100644
--- a/arch/i386/boot/memory.c
+++ b/arch/i386/boot/memory.c
@@ -28,11 +28,10 @@ static int detect_memory_e820(void)

do {
size = sizeof(struct e820entry);
- id = SMAP;
asm("int $0x15; setc %0"
- : "=am" (err), "+b" (next), "+d" (id), "+c" (size),
+ : "=dm" (err), "+b" (next), "=a" (id), "+c" (size),
"=m" (*desc)
- : "D" (desc), "a" (0xe820));
+ : "D" (desc), "d" (SMAP), "a" (0xe820));

/* Some BIOSes stop returning SMAP in the middle of
the search loop. We don't know exactly how the BIOS
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