Re: Unplayable framerates in game but specific kernel versions work, maybe amdgpu problem

[machion@disroot.org]

Hi again,

I have a question:

Would it be possible to make the "memory management/buffering" methodes 
switchable through a conf file (obviously amdgpu.conf)?
So that I don't have to keep an old kernel version installed just to 
play my game.

Marion


Am 2025-06-17 11:42, schrieb machion@disroot.org:
> I feared that.
> 
> It seems a crazy problem, when many people are affected and in opposite 
> ways.
> This ReBAR/UEFI thing is also new to me, but I don't have this on my 
> system either (using BIOS/MBR).
> 
> I hope, it can be fixed for all scenarios.
> 
> Marion
> 
> Am 2025-06-16 15:29, schrieb Alex Deucher:
>> On Fri, Jun 13, 2025 at 3:38 PM <machion@disroot.org> wrote:
>>> 
>>> Hi,
>>> sorry for the delay.
>>> Besides less time, I had to make myself familiar with bisecting and
>>> again kernel compiling. Last time I compiled the kernel myself was
>>> around 2010 I think.
>>> 
>>> Anyway it seems I found the bad commit. The result after bisecting 10
>>> commits is:
>>> 
>>> a53d959fe660341788cb8dbc3ac3330d90a09ecf is the first bad commit
>>> commit a53d959fe660341788cb8dbc3ac3330d90a09ecf
>>> Author: Christian König <christian.koenig@amd.com>
>>> Date:   Thu Mar 20 14:46:18 2025 +0100
>>> 
>>>      drm/amdgpu: immediately use GTT for new allocations
>>> 
>>>      commit a755906fb2b8370c43e91ba437ae1b3e228e8b02 upstream.
>>> 
>>>      Only use GTT as a fallback if we already have a backing store. 
>>> This
>>>      prevents evictions when an application constantly allocates and
>>> frees new
>>>      memory.
>>> 
>>>      Partially fixes
>>>      
>>> https://gitlab.freedesktop.org/drm/amd/-/issues/3844#note_2833985.
>>> 
>>>      Signed-off-by: Christian König <christian.koenig@amd.com>
>>>      Fixes: 216c1282dde3 ("drm/amdgpu: use GTT only as fallback for
>>> VRAM|GTT")
>>>      Acked-by: Alex Deucher <alexander.deucher@amd.com>
>>>      Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
>>>      Cc: stable@vger.kernel.org
>>>      Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>>> 
>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 4 ++--
>>>   1 file changed, 2 insertions(+), 2 deletions(-)
>> 
>> Unfortunately reverting that commit will reintroduce a similar
>> performance issue for lots of other uses.  See:
>> https://gitlab.freedesktop.org/drm/amd/-/issues/3844#note_2827990
>> for a description of the fundemental problem.
>> 
>> Alex
>> 
>>> 
>>> Marion
>>> 
>>> 
>>> Am 2025-05-08 15:18, schrieb Alex Deucher:
>>> > On Thu, May 8, 2025 at 9:13 AM <machion@disroot.org> wrote:
>>> >>
>>> >> Hello kernel/driver developers,
>>> >>
>>> >> I hope, with my information it's possible to find a bug/problem in the
>>> >> kernel. Otherwise I am sorry, that I disturbed you.
>>> >> I only use LTS kernels, but I can narrow it down to a hand full of
>>> >> them,
>>> >> where it works.
>>> >>
>>> >> The PC: Manjaro Stable/Cinnamon/X11/AMD Ryzen 5 2600/Radeon HD
>>> >> 7790/8GB
>>> >> RAM
>>> >> I already asked the Manjaro community, but with no luck.
>>> >>
>>> >> The game: Hellpoint (GOG Linux latest version, Unity3D-Engine v2021),
>>> >> uses vulkan
>>> >>
>>> >> ---
>>> >>
>>> >> I came a long road of kernels. I had many versions of 5.4, 5.10, 5.15,
>>> >> 6.1 and 6.6 and and the game was always unplayable, because the frames
>>> >> where around 1fps (performance of PC is not the problem).
>>> >> I asked the mesa and cinnamon team for help in the past, but also with
>>> >> no luck.
>>> >> It never worked, till on 2025-03-29 when I installed 6.12.19 for the
>>> >> first time and it worked!
>>> >>
>>> >> But it only worked with 6.12.19, 6.12.20 and 6.12.21
>>> >> When I updated to 6.12.25, it was back to unplayable.
>>> >
>>> > Can you bisect to see what fixed it in 6.12.19 or what broke it in
>>> > 6.12.25?  For example if it was working in 6.12.21 and not working in
>>> > 6.12.25, you can bisect between 6.12.21 and .25.
>>> >
>>> > Alex
>>> >
>>> >>
>>> >> For testing I installed 6.14.4 with the same result. It doesn't work.
>>> >>
>>> >> I also compared file /proc/config.gz of both kernels (6.12.21 <>
>>> >> 6.14.4), but can't seem to see drastic changes to the graphical part.
>>> >>
>>> >> I presume it has something to do with amdgpu.
>>> >>
>>> >> If you need more information, I would be happy to help.
>>> >>
>>> >> Kind regards,
>>> >> Marion