Bug 1190200

Summary:	Severe graphics glitches in KDE applications when compositor is disabled
Product:	[openSUSE] openSUSE Tumbleweed	Reporter:	Tristan Miller <psychonaut>
Component:	Kernel	Assignee:	openSUSE Kernel Bugs <kernel-bugs>
Status:	RESOLVED DUPLICATE	QA Contact:	E-mail List <qa-bugs>
Severity:	Normal
Priority:	P5 - None	CC:	mrmazda, tiwai
Version:	Current
Target Milestone:	---
Hardware:	Other
OS:	Other
Whiteboard:
Found By:	---	Services Priority:
Business Priority:		Blocker:	---
Marketing QA Status:	---	IT Deployment:	---

Description Tristan Miller 2021-09-05 13:39:20 UTC

I normally run KDE with the compositor disabled.  In this mode, all KDE applications exhibit severe screen corruption: all new text or graphics that appear have a garbled appearance, to the extent that text is completely illegible.  The corruption sometimes disappears after a few seconds or after the window is scrolled.  The problem does not affect GTK+ applications.  The problem can be worked around by using systemsettings5 to tell KDE to enable the compositor at startup.  However, simply changing the rendering backend (XRender vs. OpenGL) has no effect.

I am using an onboard Intel HD Graphics 630 controller with the i915 driver.  I'm not sure if it's the kernel driver/firmware which is causing the problem, but based on past experience with Intel graphics glitches, I am tentatively assuming it is.

The problem occurred after updating Tumbleweed from version 20210810 to version 20210827.  (In case it's relevant, this included an update of kernel-default 5.13.8 to 5.13.12, and from kernel-firmware-i915 from 20210719 to 20210812.)  The problem persists in version 20210830.

Booting from the old 5.13.8 kernel doesn't work around the problem.  I could also try reverting kernel-firmware-i915 if I can find or build an old package.

Comment 1 Tristan Miller 2021-09-05 14:08:16 UTC

I just built and installed my own copy of kernel-firmware-20210719 (by branching <https://build.opensuse.org/package/show/openSUSE:Factory/kernel-firmware?rev=168>) and unfortunately this doesn't fix the problem.

I'm open to further suggestions for troubleshooting.

Comment 2 Felix Miata 2021-09-06 05:34:48 UTC

# inxi -CS
System:
  Host: gb250 Kernel: 5.13.13-1-default x86_64 bits: 64 Console: tty pts/3
  Distro: openSUSE Tumbleweed 20210831
CPU:
  Info: Dual Core model: Intel Core i3-7100T bits: 64 type: MT MCP cache:  L2: 3 MiB
  Speed: 800 MHz min/max: 800/3400 MHz Core speeds (MHz): 1: 800 2: 800 3: 800  4: 800
# inxi -Gay
Graphics:
  Device-1: Intel HD Graphics 630 vendor: Gigabyte driver: i915 v: kernel
  bus-ID: 00:02.0 chip-ID: 8086:5912 class-ID: 0300
  Display: x11 server: X.Org 1.20.13 compositor: kwin_x11 driver:
  loaded: modesetting unloaded: fbdev,vesa alternate: intel display-ID: :0
  screens: 1
  Screen-1: 0 s-res: 1920x1200 s-dpi: 120 s-size: 406x254mm (16.0x10.0")
  s-diag: 479mm (18.9")
  Monitor-1: DP-1 res: 1920x1200 hz: 60 dpi: 94 size: 519x324mm (20.4x12.8")
  diag: 612mm (24.1")
  OpenGL: renderer: Mesa Intel HD Graphics 630 (KBL GT2) v: 4.6 Mesa 21.2.0
  direct render: Yes

I normally keep compositor disabled in all Plasma installations, which includes host gb250. The only text corruption I've seen as yet is a little bit of horizontal lines for a second or two after selecting some text in Konsole, then selecting edit > copy from the menu bar. It is repeatable. The corruption is approximately limited to the area defined by the edit > copy menu space.

Other corruption I found was in system settings > compositor, which on first mouseover the content area the various fields overlaid each other until I forced a redraw, but the text in the fields was normal where not hidden by overlay. This too is repeatable by closing systemsettings5 before trying again.

Comment 3 Takashi Iwai 2021-09-06 06:50:43 UTC

Dup of bug 1190095?

Comment 4 Tristan Miller 2021-11-02 20:13:59 UTC

Just upgraded from openSUSE 20211008 to 20211031, which included an update from kernel-default 5.14.9 to 5.14.14.  The problem is now worse: the glitches appear even when the compositor is enabled.

Comment 5 Tristan Miller 2021-11-03 20:25:07 UTC

(In reply to Tristan Miller from comment #4)
> Just upgraded from openSUSE 20211008 to 20211031, which included an update
> from kernel-default 5.14.9 to 5.14.14.  The problem is now worse: the
> glitches appear even when the compositor is enabled.

Booting from the old 5.14.9 kernel doesn't work around the glitching problem, but booting from the old read-only snapshot does.  Also, I've found that the glitching can be avoided by running a Wayland desktop instead of X11.

(In reply to Takashi Iwai from comment #3)
> Dup of bug 1190095?

I'm not sure; the symptoms reported are similar but still different.  Bug 1190095 talks about a "slow redraw" where the screen glitches for a moment and then fixes itself.  But in my case, I wouldn't say that the redraw is "slow"; the glitches appear instantaneously when a screen area changes (e.g., via scrolling), and they generally persist until I force that area of the screen to change again, at which point the glitching either changes or (if I'm lucky) disappears.

Comment 6 Tristan Miller 2021-12-20 09:29:57 UTC

No longer reproducible for me with Tumbleweed 20211218.

Comment 7 Tristan Miller 2021-12-20 10:02:00 UTC


*** This bug has been marked as a duplicate of bug 1190095 ***