[romprefix] Fix incorrect pointer offset in undiloader.S

Commit 2422647 ("[prefix] Allow prefix to specify an arbitrary maximum
address for relocation") introduced a regression into the UNDI ROM
loader by preserving an extra register on the stack without modifying
the %sp-relative addresses used in the routine.

Fix by correcting the %sp-relative addresses to allow for the extra
preserved variable.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/arch/i386/prefix/undiloader.S b/src/arch/i386/prefix/undiloader.S
index ccdd816e6686a8120d4f3e43ae7a5027836b0bd1..74bb590415d1a3637d209222e078117202bcbcdb 100644 (file)
--- a/src/arch/i386/prefix/undiloader.S
+++ b/src/arch/i386/prefix/undiloader.S
@@ -23,8 +23,8 @@ undiloader:
        popw    %ds
        /* UNDI loader parameter structure address into %es:%di */
        movw    %sp, %bx
-       movw    %ss:18(%bx), %di
-       movw    %ss:20(%bx), %es
+       movw    %ss:22(%bx), %di
+       movw    %ss:24(%bx), %es
        /* Install to specified real-mode addresses */
        pushw   %di
        movw    %es:12(%di), %bx