Bug 19266

Summary:	UHD support seems to be broken with kernel 4.7.2-desktop-1.mga6 (tested with nouveau)
Product:	Mageia	Reporter:	Elmar Stellnberger <estellnb>
Component:	RPM Packages	Assignee:	Kernel and Drivers maintainers <kernel>
Status:	RESOLVED OLD	QA Contact:
Severity:	major
Priority:	Normal	CC:	ghibomgx
Version:	Cauldron
Target Milestone:	---
Hardware:	x86_64
OS:	Linux
URL:	http://www.elstel.org/software/hunt-for-4K-UHD-2160p.html.en
Whiteboard:
Source RPM:		CVE:
Status comment:
Bug Depends on:
Bug Blocks:	19270
Attachments:	Xorg.0.log when booting with my xorg.conf (known good under Arch since 4.6.0) xorg.conf for the Xorg.0.log.old from above

Description Elmar Stellnberger 2016-08-30 20:27:23 CEST

Today I have installed Mageia 6 on my FTS Celsius H270 notebook. Its Nvidia Quadro FX 770M is usually known to support UHD (3840x2160) well under Windows and Linux from 4.5.0 on. However today with kernel 4.7.2-desktop-1.mga6 as currently shipped with Mageia 6 it was not possible to achieve any UHD mode. When I tried to deploy my current xorg.conf as used under Arch/vanilla on the very same machine not even NumLock was working after start of the Xorg server. When I tried to manually configure a known good UHD modeline my iiyama X47071UHSU stayed 'without signal' (known to work at least since 4.6.0 otherwise) while the integrated LVDS started to show screen distortions.
I do not know what is causing these issues though all of it seems a bit strange to me. I have been following the kernel since 4.6.0 and all intermediate kernels I have compiled did feature UHD well. Perhaps just the intermediate 4.7.2 is a broken commit. That is why I would suggest to wait for 4.8.0 as even kernel versions are also officially stable (afaik). The current kernel has some other bad issues (Bug 19226) and I`d suggest to simply wait with the release of Mageia 6 for 4.8.0.
Perhaps not only nouveau is affected but drm or some more basic graphics features. On the u2868pqu over VGA I could lately achieve no more than 2560x1200 with Mageia 6 / latest instead of 2560x1440 as last year on my PB Dots E2 with KaOS.
If things should get worse we would need to examine all patches as applied on mga6 kernels; however I would hope that 4.8.0 will resolve all these issues.

Comment 1 Elmar Stellnberger 2016-08-30 20:28:47 CEST

Created attachment 8379 [details]
Xorg.0.log when booting with my xorg.conf (known good under Arch since 4.6.0)

Comment 2 Elmar Stellnberger 2016-08-30 20:29:31 CEST

Created attachment 8380 [details]
xorg.conf for the Xorg.0.log.old from above

Elmar Stellnberger 2016-08-30 21:39:58 CEST

Blocks: (none) => 19270

Rémi Verschelde 2016-08-31 09:29:19 CEST

Assignee: bugsquad => kernel

Comment 3 Elmar Stellnberger 2016-08-31 09:32:45 CEST

I am currently not absolutely sure whether this is a kernel issue or whether it is related to Xorg in userspace; however I can test for it soon trying to boot Mageia 6 with my current 4.8.0-rc4 configured by Arch; I will report you back the results.

Comment 4 Elmar Stellnberger 2016-08-31 11:39:03 CEST

definitely kernel related as 4.8.0-rc4-ARCH-00609-g6db4082+radeon patch worked like expected in UHD mode for nouveau. The next thing to test would likely be a vanilla of the same version; you may notify me if you think this would be a good idea because currently I am bisecting Bug 19226.

Comment 5 Elmar Stellnberger 2016-09-03 19:07:06 CEST

definitely an issue of kernel 4.7.2. I have tried it with a vanilla (perhaps there are other graphics related issues as well with this kernel as neither sddm nor gdm succeeded to do any graphics output on an elder PIV system with it; nonetheless I see no sense in debugging it much more as I simply won`t use a kernel with broken UHD support). I`d believe that kernel 4.7.2-1 would be no good choice for a release as there are some other issues as well - and you can not backport everything; pls. wait for 4.8.0!

Comment 6 Giuseppe Ghibò 2016-10-19 15:19:31 CEST

Does that still happens to you? As to me works in 4K (3820x2160), either with internal as the external 4K display, using intel driver as well as nvidia drivers (not nouveau). Tested with kernel-desktop 4.7.4, 4.7.5, 4.7.6, 4.7.7 and 4.8.2-mga2.

CC: (none) => ghibomgx

Comment 7 sturmvogel 2022-05-29 18:56:19 CEST

Mageia 6 is EOL since Sep 2019.

In MGA8 we already have kernel 5.15/5.16/5.17 series and 5.18 is rising in cauldron.

No response from TO to comment 6...closing as OLD.

Resolution: (none) => OLD
Status: NEW => RESOLVED