On Tue, Jan 05, 2010 at 04:11:26PM +0000, Mark Cave-Ayland wrote:
> Hi all,
>
> Having just upgraded from kvm-85 to qemu-kvm-0.12.1.1 on one of our
> servers, I've noticed that I am seeing block artefacts when connecting
> using VNC to the graphical VGA console of a WinXP guest.
>
> Looking at the VNC output, what I am seeing is that instead of updating
> some parts of the screen which require a redraw, they are just being
> replaced by light grey blocks of around 16x16 pixels. Generally, but not
> always, several of these blocks appear in a row. Moving the mouse over
> the relevant sections of the screen causes them to be redrawn correctly.
>
> I've tried this using both the cirrus and vga drivers, switching between
> 16/24/32 bit colour and also different resolutions and unfortunately the
> effect still remains :( Is there anything else I can do to help try and
> debug this? Again this is on an x86_64 Debian Lenny host with a 2.6.32.2
> kernel on Intel.
Mark,
Can you confirm that reverting commit
02c2b87fff97e77a1f6033fb09f53afa267c0c1e fixes the problem? (patch
attached).
Anthony: its reproducible with upstream/tcg.
diff --git a/vnchextile.h b/vnchextile.h
index 432ed89..c96ede3 100644
--- a/vnchextile.h
+++ b/vnchextile.h
@@ -73,7 +73,7 @@ static void CONCAT(send_hextile_tile_, NAME)(VncState *vs,
*last_bg = bg;
}
- if (n_colors < 3 && (!*has_fg || *last_fg != fg)) {
+ if (!*has_fg || *last_fg != fg) {
flags |= 0x04;
*has_fg = 1;
*last_fg = fg;
@@ -165,6 +165,8 @@ static void CONCAT(send_hextile_tile_, NAME)(VncState *vs,
irow += ds_get_linesize(vs->ds) / sizeof(pixel_t);
}
+ /* A SubrectsColoured subtile invalidates the foreground color */
+ *has_fg = 0;
if (n_data > (w * h * sizeof(pixel_t))) {
n_colors = 4;
flags = 0x01;
