Bug 58652

Summary:	One pixel column that belongs in one monitor shows up in the other instead
Product:	DRI	Reporter:	shankao <shankao>
Component:	DRM/Radeon	Assignee:	Default DRI bug account <dri-devel>
Status:	RESOLVED MOVED	QA Contact:
Severity:	minor
Priority:	medium	CC:	grumpyrogue, hill-robert
Version:	unspecified
Hardware:	x86-64 (AMD64)
OS:	Linux (All)
Whiteboard:
i915 platform:		i915 features:

Description shankao 2012-12-22 16:02:24 UTC

I have configured the laptop screen in the left and a external monitor in the right. On the left most part of the monitor, I can see 1 column of pixels that belong to the content that is in the right most part of the laptop.

Strangely, it does not show up when I try to do a screenshot, but is quite evident when watching a fullscreen movie in the monitor, for example.

Original bug report at Ubuntu's launchpad: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+bug/1085338

Comment 1 Alex Deucher 2012-12-22 16:11:35 UTC

This is a limitation due to the way xrandr works.  It uses a single surface for all enabled displays rather than one surface per display.  The display hardware has alignment requirements that can cause this situation since we align the start address down.  The per-crtc pixmaps work should fix the issue when it finally goes into the xserver.

Comment 2 shankao 2012-12-22 16:29:34 UTC

Ok thanks. Any idea when that's planned for? :)

Comment 3 shankao 2014-01-13 00:19:46 UTC

This is still an existing problem since a couple of years in my setup, so I'll try to move it a bit to get it solved:

I wonder if there's any way on which this alignment could be off-by-one in the xrandr code for this specific case. Is there any way or place where I could have a look and try?

Thanks.

Comment 4 Alex Deucher 2014-01-13 14:12:56 UTC

(In reply to comment #3)
> This is still an existing problem since a couple of years in my setup, so
> I'll try to move it a bit to get it solved:
> 
> I wonder if there's any way on which this alignment could be off-by-one in
> the xrandr code for this specific case. Is there any way or place where I
> could have a look and try?

It's a radeon display hardware alignment requirement.

Comment 5 Alex Deucher 2014-01-13 14:13:29 UTC

*** Bug 63900 has been marked as a duplicate of this bug. ***

Comment 6 Martin Peres 2019-11-19 08:31:21 UTC

-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/drm/amd/issues/315.

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