[SeaBIOS] [Xen-devel] Regression booting winxp under Xen.

Kevin O'Connor kevin at koconnor.net
Mon Nov 3 15:59:59 CET 2014

On Mon, Nov 03, 2014 at 10:05:05AM +0000, Ian Campbell wrote:
> On Mon, 2014-11-03 at 09:59 +0000, Ian Campbell wrote:
> > I've not investigated more thoroughly yes, just posting in case
> > something obvious leaps out at someone. The automated test is currently
> > bisecting the issue, once it is done I'll let you know the result.
> If I'd read a bit further through my Monday morning INBOX I'd have
> found:
>         http://lists.xen.org/archives/html/xen-devel/2014-11/msg00001.html
> which indicates that the bisector has fingered:
>   commit 99cb8f3e9af516954b2f2fba97ce1856e3d7b93f

Sorry about that - I missed one of the stack offset conversions in the
PNP part of that change.  The fix is below and I just pushed it to
the main repo.

Thanks for catching it.

--- a/src/romlayout.S
+++ b/src/romlayout.S
@@ -286,7 +286,7 @@ entry_pnp_real:
         movw %cx, %ds
         leal BREGS_size-6+12(%esp), %eax  // %eax points to start of u16 args
         calll handle_pnp
-        movw %ax, 12(%esp)      // Modify %eax to return %ax
+        movw %ax, BREGS_eax(%esp)   // Modify %eax to return %ax
         popl %esp

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