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

[machion at 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 at 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 at 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 at amd.com>
>>      Fixes: 216c1282dde3 ("drm/amdgpu: use GTT only as fallback for
>> VRAM|GTT")
>>      Acked-by: Alex Deucher <alexander.deucher at amd.com>
>>      Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
>>      Cc: stable at vger.kernel.org
>>      Signed-off-by: Greg Kroah-Hartman <gregkh at 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 at 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