diff --git a/arch/x86/boot/video-vga.c b/arch/x86/boot/video-vga.c
index ed7aeff786b277d01b281a47c418eb5c988ea249..45bc9402aa497f7c7151a7ce3e0b419ab9454301 100644
--- a/arch/x86/boot/video-vga.c
+++ b/arch/x86/boot/video-vga.c
@@ -41,13 +41,12 @@ static __videocard video_vga;
 static u8 vga_set_basic_mode(void)
 {
 	struct biosregs ireg, oreg;
-	u16 ax;
 	u8 mode;
 
 	initregs(&ireg);
 
 	/* Query current mode */
-	ax = 0x0f00;
+	ireg.ax = 0x0f00;
 	intcall(0x10, &ireg, &oreg);
 	mode = oreg.al;