diff options
author | H. Peter Anvin <hpa@linux.intel.com> | 2009-04-01 21:19:00 -0400 |
---|---|---|
committer | H. Peter Anvin <hpa@zytor.com> | 2009-04-09 19:08:11 -0400 |
commit | 0a706db320768f8f6e43bbf73b58d2aabdc93354 (patch) | |
tree | 9e103e27c215a22fc8e10ffa2ef8deff1a5364e8 /arch/x86/boot/mca.c | |
parent | 3435d3476c5ed955d56a6216ed2d156847b3a575 (diff) |
x86, setup: "glove box" BIOS interrupts in the MCA code
Impact: BIOS proofing
"Glove box" off BIOS interrupts in the MCA code.
LKML-Reference: <49DE7F79.4030106@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Diffstat (limited to 'arch/x86/boot/mca.c')
-rw-r--r-- | arch/x86/boot/mca.c | 27 |
1 files changed, 12 insertions, 15 deletions
diff --git a/arch/x86/boot/mca.c b/arch/x86/boot/mca.c index 911eaae5d69..a95a531148e 100644 --- a/arch/x86/boot/mca.c +++ b/arch/x86/boot/mca.c | |||
@@ -2,6 +2,7 @@ | |||
2 | * | 2 | * |
3 | * Copyright (C) 1991, 1992 Linus Torvalds | 3 | * Copyright (C) 1991, 1992 Linus Torvalds |
4 | * Copyright 2007 rPath, Inc. - All Rights Reserved | 4 | * Copyright 2007 rPath, Inc. - All Rights Reserved |
5 | * Copyright 2009 Intel Corporation; author H. Peter Anvin | ||
5 | * | 6 | * |
6 | * This file is part of the Linux kernel, and is made available under | 7 | * This file is part of the Linux kernel, and is made available under |
7 | * the terms of the GNU General Public License version 2. | 8 | * the terms of the GNU General Public License version 2. |
@@ -16,26 +17,22 @@ | |||
16 | 17 | ||
17 | int query_mca(void) | 18 | int query_mca(void) |
18 | { | 19 | { |
19 | u8 err; | 20 | struct biosregs ireg, oreg; |
20 | u16 es, bx, len; | 21 | u16 len; |
21 | 22 | ||
22 | asm("pushw %%es ; " | 23 | initregs(&ireg); |
23 | "int $0x15 ; " | 24 | ireg.ah = 0xc0; |
24 | "setc %0 ; " | 25 | intcall(0x15, &ireg, &oreg); |
25 | "movw %%es, %1 ; " | 26 | |
26 | "popw %%es" | 27 | if (oreg.eflags & X86_EFLAGS_CF) |
27 | : "=acd" (err), "=acdSD" (es), "=b" (bx) | ||
28 | : "a" (0xc000)); | ||
29 | |||
30 | if (err) | ||
31 | return -1; /* No MCA present */ | 28 | return -1; /* No MCA present */ |
32 | 29 | ||
33 | set_fs(es); | 30 | set_fs(oreg.es); |
34 | len = rdfs16(bx); | 31 | len = rdfs16(oreg.bx); |
35 | 32 | ||
36 | if (len > sizeof(boot_params.sys_desc_table)) | 33 | if (len > sizeof(boot_params.sys_desc_table)) |
37 | len = sizeof(boot_params.sys_desc_table); | 34 | len = sizeof(boot_params.sys_desc_table); |
38 | 35 | ||
39 | copy_from_fs(&boot_params.sys_desc_table, bx, len); | 36 | copy_from_fs(&boot_params.sys_desc_table, oreg.bx, len); |
40 | return 0; | 37 | return 0; |
41 | } | 38 | } |