Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
kernel update and amdgpu breaks X
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware
View previous topic :: View next topic  
Author Message
rvj
n00b
n00b


Joined: 24 Oct 2018
Posts: 11

PostPosted: Fri Feb 28, 2025 4:03 am    Post subject: kernel update and amdgpu breaks X Reply with quote

In a recent system update, the kernel went from vmlinuz-6.6.74-gentoo to vmlinuz-6.12.16-gentoo. In the process, wayland / X has broken (although rc-status reports that display-manager is running). The new kernel boots into a default VT1 terminal; VT7 shows a black screen with a blinking underscore.

Booting with the older kernel on the otherwise identical updated system provides a fully functioning display-manager / sddm.

(Also, a different computer with similar setup but different graphics chip upgraded with no problems.)

One detail of this setup that is most likely relevant: IrEFInd is the boot manager, and this requires EFI framebuffer support to be able to display later portions of the boot process, loaded directly into the kernel as a firmware blob, not loaded as a module. All dozen amdgpu/renoir_* blobs have been included. For older versions of the kernel, this worked as required.

To help diagnose, I ran startx and recorded the Xorg startup log, comparing the performance using the fully functional older kernel and the problematic new kernel. Both logs give comparable output, until the newer kernel ends with

[ 48.197] (EE) Device(s) detected, but none match those in the config file.
[ 48.197] (EE)
Fatal server error:
[ 48.197] (EE) no screens found(EE)
[ 48.197] (EE)
Please consult the The X.Org Foundation support at http://wiki.x.org for help.
[ 48.197] (EE) Please also check the log file at "/home/rvj/.local/share/xorg/Xorg.0.log" for additional information.
[ 48.197] (EE)
[ 48.199] (EE) Server terminated with error (1). Closing log file.

whereas the older kernel continues with

[ 24.695] (II) FBDEV(0): Creating default Display subsection in Screen section
"Default Screen Section" for depth/fbbpp 24/32
[ 24.695] (==) FBDEV(0): Depth 24, (==) framebuffer bpp 32
[ 24.695] (==) FBDEV(0): RGB weight 888
[ 24.695] (==) FBDEV(0): Default visual is TrueColor
[ 24.695] (==) FBDEV(0): Using gamma correction (1.0, 1.0, 1.0)
[ 24.695] (II) FBDEV(0): hardware: EFI VGA (video memory: 8100kB)
etc.

Here is the successful Xorg log with the older kernel: https://bpa.st/L5XQ

Here is the failed Xorg log with the newer kernel: https://bpa.st/6VDA

Please advise … any further diagnostics, or files to the posted?

Thanks!
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 54940
Location: 56N 3W

PostPosted: Fri Feb 28, 2025 7:00 pm    Post subject: Reply with quote

rvj,

Quote:
Here is the successful Xorg log with the older kernel: https://bpa.st/L5XQ


Lets start there.
The graphics card listed there is
Code:
[    24.421] (--) PCI:*(4@0:0:0) 1002:164c:1043:880a rev 194, Mem @ 0xd0000000/268435456, 0xe0000000/2097152, 0xfcb00000/524288, I/O @ 0x0000e000/256

Luoking up 002:164c: on cateee.net, it needs DRM_AMDGPU in the kernel. Hold that thought.

Code:
[    24.428] (II) Loading /usr/lib64/xorg/modules/drivers/ati_drv.so
[    24.428] (II) Module ati: vendor="X.Org Foundation"
...
[    24.693] (II) RADEON: Driver for ATI/AMD Radeon chipsets:

That's the older Radeon driver, which is not for you.

Code:
[    24.694] (EE) open /dev/dri/card0: No such file or directory

Tells that the drm module for your GPU is not available to you, or at least, its not loaded into the kernel.

Eventually, the X server falls back to
Code:
[    24.695] (II) FBDEV(0): Creating default Display subsection in Screen section
which does not use your GPU at all. The CPU does all the work that the GPU should be doing.

See the AMDGPU wiki page. Try that on the one that does not work at all, then do it to the 'working' system.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
pietinger
Moderator
Moderator


Joined: 17 Oct 2006
Posts: 5451
Location: Bavaria

PostPosted: Fri Feb 28, 2025 7:40 pm    Post subject: Re: kernel update and amdgpu breaks X Reply with quote

rvj wrote:
In a recent system update, the kernel went from vmlinuz-6.6.74-gentoo to vmlinuz-6.12.16-gentoo. [...] All dozen amdgpu/renoir_* blobs have been included. For older versions of the kernel, this worked as required.

Maybe you will need newer/other firmware files for AMDGPU with your new kernel.

You can check easily: Boot out GentooLiveCD and do a "dmesg | grep firmware". Notice all files and compare this list with your setting in CONFIG_EXTRA_FIRMWARE=

(see also here: https://wiki.gentoo.org/wiki/User:Pietinger/Tutorials/Manual_kernel_configuration#Before_you_start )
_________________
https://wiki.gentoo.org/wiki/User:Pietinger
Back to top
View user's profile Send private message
rvj
n00b
n00b


Joined: 24 Oct 2018
Posts: 11

PostPosted: Sat Mar 01, 2025 12:50 am    Post subject: Reply with quote

:D Thanks for the advice! I've not heard of cateee.net; very interesting! The suggestion of turning on DRM_AMDGPU in the kernel fixed the problem. I had not appreciated the significance of DRM until now.
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 54940
Location: 56N 3W

PostPosted: Sat Mar 01, 2025 9:46 am    Post subject: Reply with quote

rvj,

dmes should show amdgpudrmfb in use as the framebuffer console
The Xorg log should have lots of lines starting AMDGPU
Just to make sure.

It should also be a lot faster drawing the screen than FBDEV was.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum