x86, setup: "glove box" BIOS interrupts in the core boot code
Impact: BIOS proofing
"Glove box" off BIOS interrupts in the core boot code.
LKML-Reference: <49DE7F79.4030106@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/boot/a20.c b/arch/x86/boot/a20.c
index 7c19ce8..64a31a6 100644
--- a/arch/x86/boot/a20.c
+++ b/arch/x86/boot/a20.c
@@ -2,7 +2,7 @@
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright 2007-2008 rPath, Inc. - All Rights Reserved
- * Copyright 2009 Intel Corporation
+ * Copyright 2009 Intel Corporation; author H. Peter Anvin
*
* This file is part of the Linux kernel, and is made available under
* the terms of the GNU General Public License version 2.
@@ -90,8 +90,11 @@
static void enable_a20_bios(void)
{
- asm volatile("pushfl; int $0x15; popfl"
- : : "a" ((u16)0x2401));
+ struct biosregs ireg;
+
+ initregs(&ireg);
+ ireg.ax = 0x2401;
+ intcall(0x15, &ireg, NULL);
}
static void enable_a20_kbc(void)