Bug 90099

Summary:	One pixel high lines appearing all over the place on RS780
Product:	xorg	Reporter:	Juraj Fiala <jurf>
Component:	Driver/Radeon	Assignee:	xf86-video-ati maintainers <xorg-driver-ati>
Status:	RESOLVED MOVED	QA Contact:	Xorg Project Team <xorg-team>
Severity:	normal
Priority:	medium	CC:	jurf
Version:	unspecified
Hardware:	Other
OS:	All
Whiteboard:
i915 platform:		i915 features:

Description Juraj Fiala 2015-04-19 15:32:12 UTC

I have an ATI Mobility Radeon 3200 on my HP Compaq 6735s.

Important: this bug is a regression. It used to work flawlessly. I don't know what's causing the bug or when specifically it started, but I know that Ubuntu 14.04 hasn't got this bug, but 14.10 has. Now running Arch Linux, and it's still there.

I am unable record the bug or capture it on a screenshot, so I'll try to describe it.

I have these thin, usually white lines appearing all over the place, with their length ranging from a couple to a couple hundred pixels. Always horizontal. They disappear quickly too, so sometimes I'm not even sure what colour they are.

The weirdest thing is that they only appear when the system is cold (e.g. on cold boot), so they're the most in the boot screen and the login screen. Happens in a TTY, in X and in Wayland. The hotter the system gets, the shorter they are. I don't usually see them at all, but when you stare at the display, you sense that something is not right. There's that odd flicker appearing here and there.

About the colour: they are usually white, but not always. I swear I saw colourful ones here and there. Also, when I look at the blue GNOME background, I don't see any white lines, but there is some sort of flickering.

My guess is that one pixel sort of stretches itself, covering other ones. As if the rendering lagged and printed the same pixel a couple of times. I think that's the most accurate description I can give.

Also, this only happens in the built-in display. I have a LCD plugged in right now, and it's fine.

If you need any more info, just ask.

Thanks.

Comment 1 Alex Deucher 2015-04-19 15:53:30 UTC

Please make sure your kernel has this patch:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=72edd83cc9e5819ed1ee771519143d7594e059f0

Comment 2 Juraj Fiala 2015-04-19 16:02:57 UTC

I don't think it does. The source file are here: https://projects.archlinux.org/svntogit/packages.git/tree/trunk?h=packages/linux

Besides, I'm using linux-ck from an unofficial repository (repo-ck).

I can try to compile it from source if necessary.

Comment 3 Juraj Fiala 2015-04-19 16:11:21 UTC

Although when I look at the kernel source that the PKGBUILD uses to compile linux, it does include it, so my kernel has it too: https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/tree/drivers/gpu/drm/radeon/radeon_display.c?id=refs/tags/v3.19.5

Comment 4 Juraj Fiala 2015-04-23 15:04:55 UTC

So yeah, I definitely have that patch in my kernel.

Comment 5 Juraj Fiala 2015-06-15 16:17:17 UTC

Should I also report this on the kernel bugtracker?

Comment 6 Michel Dänzer 2015-06-16 00:28:44 UTC

(In reply to Juraj Fiala from comment #5)
> Should I also report this on the kernel bugtracker?

No, we can actually track kernel driver bugs better here as well.

Comment 7 Martin Peres 2019-11-19 07:50:08 UTC

-- GitLab Migration Automatic Message --

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

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