diff --git a/xen/arch/i386/entry.S b/xen/arch/i386/entry.S
index 155ad23c4d..a0ca4b4e27 100644
--- a/xen/arch/i386/entry.S
+++ b/xen/arch/i386/entry.S
@@ -406,7 +406,11 @@ create_bounce_frame:
         jz   1f /* jump if returning to an existing ring-1 activation */
         /* obtain ss/esp from TSS -- no current ring-1 activations */
         movzwl PROCESSOR(%ebx),%eax
-        shll $8,%eax /* multiply by 256 */
+        /* next 4 lines multiply %eax by 8320, which is sizeof(tss_struct) */
+        movl %eax, %ecx
+        shll $7, %ecx
+        shll $13, %eax
+        addl %ecx,%eax
         addl $init_tss + 12,%eax
         movl (%eax),%esi /* tss->esp1 */
 FAULT6: movl 4(%eax),%ds /* tss->ss1  */
diff --git a/xen/include/asm-i386/processor.h b/xen/include/asm-i386/processor.h
index 2968e2e4e9..aa5048c6ec 100644
--- a/xen/include/asm-i386/processor.h
+++ b/xen/include/asm-i386/processor.h
@@ -375,7 +375,7 @@ struct tss_struct {
     unsigned short	trace, bitmap;
     unsigned long	io_bitmap[IO_BITMAP_SIZE+1];
     /*
-     * pads the TSS to be cacheline-aligned (size is 0x100)
+     * pads the TSS to be cacheline-aligned (total size is 0x2080)
      */
     unsigned long __cacheline_filler[5];
 };