[Qemu-devel] Re: [PATCH 00/23] VGA cleanup

[Juan Quintela <quintela@redhat.com>]

Pierre Riteau <Pierre.Riteau@irisa.fr> wrote:
>>> This patchset introduced a bug. I noticed today that I can't boot an
>>> installation disk of ubuntu-9.04-server-i386.
>>> After entering the install program ("Install Ubuntu Server"), I just
>>> get a black background with gray vertical lines.
>>>
>>> More specifically, from oldest to newest commit:
>>> 86948bb104f419db9af6b621b85703e8f0d3234c works
>>> f705db9df04c6491f242a5a4585dfe72b708f197 throws a warning about an
>>> uninitialized variable (had to disable werror) but works
>>
>> could you post the error message?  I didn't have that problem.
>
> /mnt/qemu/hw/cirrus_vga.c: In function 'cirrus_vga_ioport_read':
> /mnt/qemu/hw/cirrus_vga.c:2656: warning: 'val' may be used
> uninitialized in this function

This is fixed on a later, patch, sorry :(

> I'm using ./configure --target-list=i386-softmmu --disable-werror, gcc
> is version 4.3.2 (from Debian Lenny).
>
>>
>>> 22286bc6468adac10b2eb7e603f1a8ba524bfb03 throws a warning about an
>>> uninitialized variable (had to disable werror) and doesn't work
>>> b863d51490b7c6e339c9565eda786cadc1218d48 compiles without warning and
>>> doesn't work
>>
>> Weird, it did worked for me.  Could you post what command line did you
>> use?  I tested with fedora + win XP.
>
> qemu -cdrom ~/ubuntu-9.04-server-i386.iso -boot d
>
>>
>>> So 22286bc6468adac10b2eb7e603f1a8ba524bfb03 must be the problematic
>>> commit.
>>
>> Thanks, will take a look.

could you check this patch?
(still not sure why it worked for fedora + xp for me)

>From 97869744f37ccd2846e3edcc1ad9f582d9bea1c6 Mon Sep 17 00:00:00 2001
From: Juan Quintela <quintela@redhat.com>
Date: Wed, 16 Sep 2009 15:44:49 +0200
Subject: [PATCH] cirrus_vga: also assign gr0/1 when writting shadow_gr0/1


Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 hw/cirrus_vga.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/hw/cirrus_vga.c b/hw/cirrus_vga.c
index 004ae7d..9dfe76a 100644
--- a/hw/cirrus_vga.c
+++ b/hw/cirrus_vga.c
@@ -1490,9 +1490,11 @@ cirrus_vga_write_gr(CirrusVGAState * s, unsigned reg_index, int reg_value)
 #endif
     switch (reg_index) {
     case 0x00:			// Standard VGA, BGCOLOR 0x000000ff
+	s->vga.gr[reg_index] = reg_value & gr_mask[reg_index];
 	s->cirrus_shadow_gr0 = reg_value;
 	break;
     case 0x01:			// Standard VGA, FGCOLOR 0x000000ff
+	s->vga.gr[reg_index] = reg_value & gr_mask[reg_index];
 	s->cirrus_shadow_gr1 = reg_value;
 	break;
     case 0x02:			// Standard VGA
-- 
1.6.2.5