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From: "Timothy Miller" <tmiller10@cfl.rr.com>
To: <linux-kernel@vger.kernel.org>
Subject: Ah!  Found a bug in radeonfb.c!
Date: Fri, 12 Mar 2004 01:33:01 -0500
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I was WONDERING why certain things would get corrupted on the screen when
using the radeon framebuffer driver.  I've been seeing a number of
off-by-one errors.

First of all, the kernel source I'm looking at is 2.4.22-gentoo-r7.

Anyhow, here's the deal.  Look at the function 'fbcon_radeon_bmove'.  I'm
having to type this in by hand due to circumstances, so, here's something
that looks vaguely like a patch but which will require people to actually
look at (I've never submitted a patch before, so let's just discuss it
first):

line 4399:
    if (srcy < dsty) {
-        srcy += height;
-        dsty += height;
+        srcy += height-1;
+        dsty += height-1;
    } else


line 4404:
    if (srcx < dstx) {
-        srcx += width;
-        dstx += width;
+        srcx += width-1;
+        dstx += width-1;
    }