Commit 71351b98 authored Aug 23, 2007 by H. Peter Anvin

[x86 setup] Make sure AH=00h when setting a video mode



Passing a u8 into a register doesn't mean gcc will zero-extend it.
Also, don't depend on thhe register not to change.

Per bug report from Saul Tamari.

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

parent b015124e

arch/i386/boot/video-vga.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -73,9 +73,10 @@ static u8 vga_set_basic_mode(void)
		mode = 3;

		/* Set the mode */
		ax = mode;
		asm volatile(INT10
		: : "a" (mode)
		: "ebx", "ecx", "edx", "esi", "edi");
		: "+a" (ax)
		: : "ebx", "ecx", "edx", "esi", "edi");
		do_restore = 1;
		return mode;
		}