diff --git a/disk/i386/pc/biosdisk.c b/disk/i386/pc/biosdisk.c
index 0f75dba5f..92198e591 100644
--- a/disk/i386/pc/biosdisk.c
+++ b/disk/i386/pc/biosdisk.c
@@ -33,29 +33,29 @@ static int grub_biosdisk_rw_int13_extensions (int ah, int drive, void *dap);
 
 static int grub_biosdisk_get_num_floppies (void)
 {
-  struct grub_cpu_int_registers regs;
+  struct grub_bios_int_registers regs;
   int drive;
 
   /* reset the disk system first */
-  regs.ax = 0;
-  regs.dx = 0;
+  regs.eax = 0;
+  regs.edx = 0;
   regs.flags = GRUB_CPU_INT_FLAGS_DEFAULT;
 
-  grub_cpu_interrupt (0x13, &regs);
+  grub_bios_interrupt (0x13, &regs);
 
   for (drive = 0; drive < 2; drive++)
     {
       regs.flags = GRUB_CPU_INT_FLAGS_DEFAULT | GRUB_CPU_INT_FLAGS_CARRY;
-      regs.dx = drive;
+      regs.edx = drive;
 
       /* call GET DISK TYPE */
-      regs.ax = 0x1500;
-      grub_cpu_interrupt (0x13, &regs);
+      regs.eax = 0x1500;
+      grub_bios_interrupt (0x13, &regs);
       if (regs.flags & GRUB_CPU_INT_FLAGS_CARRY)
 	break;
 
       /* check if this drive exists */
-      if (!(regs.ax & 0x300))
+      if (!(regs.eax & 0x300))
 	break;
     }
 
@@ -71,16 +71,16 @@ static int grub_biosdisk_get_num_floppies (void)
 static int 
 grub_biosdisk_rw_int13_extensions (int ah, int drive, void *dap)
 {
-  struct grub_cpu_int_registers regs;
-  regs.ax = ah << 8;
+  struct grub_bios_int_registers regs;
+  regs.eax = ah << 8;
   /* compute the address of disk_address_packet */
   regs.ds = (((grub_addr_t) dap) & 0xffff0000) >> 4;
-  regs.si = (((grub_addr_t) dap) & 0xffff);
-  regs.dx = drive;
+  regs.esi = (((grub_addr_t) dap) & 0xffff);
+  regs.edx = drive;
   regs.flags = GRUB_CPU_INT_FLAGS_DEFAULT;
 
-  grub_cpu_interrupt (0x13, &regs);
-  return regs.ax >> 8;
+  grub_bios_interrupt (0x13, &regs);
+  return (regs.eax >> 8) & 0xff;
 }
 
 static int
diff --git a/include/grub/i386/pc/int.h b/include/grub/i386/pc/int.h
index b8cbe3260..e1c463925 100644
--- a/include/grub/i386/pc/int.h
+++ b/include/grub/i386/pc/int.h
@@ -21,17 +21,18 @@
 
 #include <grub/symbol.h>
 
-struct grub_cpu_int_registers
+struct grub_bios_int_registers
 {
-  grub_uint16_t bx;
+  grub_uint32_t eax;
   grub_uint16_t es;
-  grub_uint16_t cx;
-  grub_uint16_t ax;
-  grub_uint16_t dx;
   grub_uint16_t ds;
-  grub_uint16_t di;
   grub_uint16_t flags;
-  grub_uint16_t si;
+  grub_uint16_t dummy;
+  grub_uint32_t ebx;
+  grub_uint32_t ecx;
+  grub_uint32_t edi;
+  grub_uint32_t esi;
+  grub_uint32_t edx;
 };
 
 #define  GRUB_CPU_INT_FLAGS_CARRY     0x1
@@ -45,6 +46,7 @@ struct grub_cpu_int_registers
 #define  GRUB_CPU_INT_FLAGS_OVERFLOW  0x800
 #define  GRUB_CPU_INT_FLAGS_DEFAULT   GRUB_CPU_INT_FLAGS_INTERRUPT
 
-void EXPORT_FUNC (grub_cpu_interrupt) (grub_uint8_t intno, struct grub_cpu_int_registers *regs);
+void EXPORT_FUNC (grub_bios_interrupt) (grub_uint8_t intno,
+					struct grub_bios_int_registers *regs);
 
 #endif
diff --git a/kern/i386/pc/startup.S b/kern/i386/pc/startup.S
index 815686502..cb6ef32a6 100644
--- a/kern/i386/pc/startup.S
+++ b/kern/i386/pc/startup.S
@@ -2068,73 +2068,96 @@ FUNCTION(grub_pxe_call)
 	popl	%ebp
 	ret
 
-FUNCTION(grub_cpu_interrupt)
+FUNCTION(grub_bios_interrupt)
 	pushl    %ebp
-	pushl    %esi
-	pushl    %edi
-	pushl    %ebx
+	pushl    %ecx
+	pushl    %eax
 	pushl    %edx
+	
 	movb     %al, intno
-	movl     %edx, %esi
+	movl	 (%edx), %eax
+	movl	 %eax, LOCAL(bios_register_eax)
+	movw	 4(%edx), %ax
+	movw	 %ax, LOCAL(bios_register_es)
+	movw	 6(%edx), %ax
+	movw	 %ax, LOCAL(bios_register_ds)
+	movw	 8(%edx), %ax
+	movw	 %ax, LOCAL(bios_register_flags)
 
-	movl     0(%esi), %ebx
-	movl	 4(%esi), %ecx
-	movl     8(%esi), %edx
-	movl     12(%esi), %edi
-	movw     16(%esi), %si
+	movl 	12(%edx), %ebx
+	movl 	16(%edx), %ecx
+	movl 	20(%edx), %edi
+	movl 	24(%edx), %esi
+	movl 	28(%edx), %edx
 
 	call    prot_to_real
 	.code16
-	movl    %edi, %eax
-	shrl    $16, %eax
-	push    %ax
 
-	movl    %ebx, %eax
-	shrl    $16, %eax
-	movw    %ax, %es
-	
-	movl    %edx, %eax
-	shrl    $16, %eax
-	movw    %ax, %ds
+	mov	%ds, %ax
+	push	%ax
 
-	movl    %ecx, %eax
-	shrl    $16, %eax
+	/* movw imm16, %ax*/
+	.byte	0xb8
+LOCAL(bios_register_es):
+	.short 	0
+	movw	%ax, %es
+	/* movw imm16, %ax*/
+	.byte	0xb8
+LOCAL(bios_register_ds):
+	.short 	0
+	movw	%ax, %ds
 
+	/* movw imm16, %ax*/
+	.byte	0xb8
+LOCAL(bios_register_flags):
+	.short 	0
+	push	%ax
 	popf
+
+	/* movl imm32, %eax*/
+	.byte	0x66, 0xb8
+LOCAL(bios_register_eax):
+	.long 	0
+	
+	/* int imm8.  */
 	.byte   0xcd
 intno:	
 	.byte   0
 
+	movl 	%eax, %cs:LOCAL(bios_register_eax)
+	movw	%ds, %ax
+	movw 	%ax, %cs:LOCAL(bios_register_ds)
+	pop 	%ax
+	mov	%ax, %ds
 	pushf
-	andl    $0xffff, %ebx
-	andl    $0xffff, %ecx
-	andl    $0xffff, %edx
-	andl    $0xffff, %edi
-
-	shll    $16, %eax
-	orl     %eax, %ecx
-
-	movw    %ds, %ax
-	shll    $16, %eax
-	orl     %eax, %edx
-
-	pop     %ax
-	shll    $16, %eax
-	orl     %eax, %edi
+	pop	%ax
+	movw	%ax, LOCAL(bios_register_flags)
+	mov 	%es, %ax
+	movw	%ax, LOCAL(bios_register_es)
 
 	DATA32  call	real_to_prot
 	.code32
-	pushl    %esi
-	movl     4(%esp), %esi
-	movl     %ebx, 0(%esi)
-	movl     %ecx, 4(%esi)
-	movl     %edx, 8(%esi)
-	movl     %edi, 12(%esi)
-	popl     %eax
-	movw     %ax, 16(%esi)
-	popl     %eax
-	popl	 %ebx
-	popl	 %edi
-	popl	 %esi
-	popl     %ebp
+
+	popl    %eax
+
+	movl 	%ebx, 12(%eax)
+	movl 	%ecx, 16(%eax)
+	movl 	%edi, 20(%eax)
+	movl 	%esi, 24(%eax)
+	movl 	%edx, 28(%eax)
+
+	movl     %eax, %edx
+
+	movl	 LOCAL(bios_register_eax), %eax
+	movl	 %eax, (%edx)
+	movw	 LOCAL(bios_register_es), %ax
+	movw	 %ax, 4(%edx)
+	movw	 LOCAL(bios_register_ds), %ax
+	movw	 %ax, 6(%edx)
+	movw	 LOCAL(bios_register_flags), %ax
+	movw	 %ax, 8(%edx)
+
+	popl    %eax
+	popl    %ecx
+	popl    %ebp
 	ret