PROBLEM: AMD Ryzen 9 7950X iGPU - Blinking Issue

[Hamza Mahfooz]

On 6/3/23 10:52, Felix Richter wrote:
> Hi Guys,
> 
> sorry for the silence from my side. I had a lot of things to take care 
> of after returning from vacation. Also I had to wait on the zfs modules 
> to be updated to support kernel 6.3 for further testing.
> 
> The bad news is that I am still experiencing issues. I have been able to 
> get a reproducible trigger for the buggy behavior. The moment I take a 
> screenshot or any other program like `wdisplays` accesses the screen 
> buffer the screen starts flickering. The only way to reset it is to 
> reboot the machine or log out of the desktop.
> 
> With this I did a bisection to figure out which commit is responsible 
> for this. I attached the logs to the mail. The short version is that I 
> identified commit 81d0bcf9900932633d270d5bc4a54ff599c6ebdb as the 
> culprit. Seems that there are side effects of having more flexible 
> buffer placement for the case of the internal GPU. To verify that this 
> actually is the cause of the issue I built the current archlinux kernel 
> with an extra patch to revert the commit: 
> https://github.com/ju6ge/linux/tree/v6.3.5-ju6ge. The result is that be 
> bug is fixed!
> 
> Now if this is the desired long term fix I do not know …

Can you provide a dmidecode of your RAM (i.e. # dmidecode --type=memory)?

The current trend seems to suggest that if you have 64 or more gigs of
RAM, you will probably still experience issues with S/G mode enabled
even with my fix applied.

> 
> Kind regards,
> Felix Richter
> 
> On 02.05.23 16:12, Linux regression tracking (Thorsten Leemhuis) wrote:
>> On 02.05.23 15:48, Felix Richter wrote:
>>> On 5/2/23 15:34, Linux regression tracking (Thorsten Leemhuis) wrote:
>>>> On 02.05.23 15:13, Alex Deucher wrote:
>>>>> On Tue, May 2, 2023 at 7:45 AM Linux regression tracking (Thorsten
>>>>> Leemhuis)<regressions at leemhuis.info>  wrote:
>>>>>
>>>>>> On 30.04.23 13:44, Felix Richter wrote:
>>>>>>> Hi,
>>>>>>>
>>>>>>> I am running into an issue with the integrated GPU of the Ryzen 9
>>>>>>> 7950X. It seems to be a regression from kernel version 6.1 to 6.2.
>>>>>>> The bug materializes in from of my monitor blinking, meaning it
>>>>>>> turns full white shortly. This happens very often so that the
>>>>>>> system becomes unpleasant to use.
>>>>>>>
>>>>>>> I am running the Archlinux Kernel:
>>>>>>> The Issue happens on the bleeding edge kernel: 6.2.13
>>>>>>> Switching back to the LTS kernel resolves the issue: 6.1.26
>>>>>>>
>>>>>>> I have two monitors attached to the system. One 42 inch 4k Display
>>>>>>> and a 24 inch 1080p Display and am running sway as my desktop.
>>>>>>>
>>>>>>> Let me know if there is more information I could provide to help
>>>>>>> narrow down the issue.
>>>>>> Thanks for the report. To be sure the issue doesn't fall through the
>>>>>> cracks unnoticed, I'm adding it to regzbot, the Linux kernel 
>>>>>> regression
>>>>>> tracking bot:
>>>>>>
>>>>>> #regzbot ^introduced v6.1..v6.2
>>>>>> #regzbot title drm: amdgpu: system becomes unpleasant to use after
>>>>>> monitor starts blinking and turns full white
>>>>>> #regzbot ignore-activity
>>>>>>
>>>>>> This isn't a regression? This issue or a fix for it are already
>>>>>> discussed somewhere else? It was fixed already? You want to clarify
>>>>>> when
>>>>>> the regression started to happen? Or point out I got the title or
>>>>>> something else totally wrong? Then just reply and tell me -- ideally
>>>>>> while also telling regzbot about it, as explained by the page 
>>>>>> listed in
>>>>>> the footer of this mail.
>>>>>>
>>>>>> Developers: When fixing the issue, remember to add 'Link:' tags
>>>>>> pointing
>>>>>> to the report (the parent of this mail). See page linked in footer 
>>>>>> for
>>>>>> details.
>>>>> This sounds exactly like the issue that was fixed in this patch which
>>>>> is already on it's way to Linus:
>>>>> https://gitlab.freedesktop.org/agd5f/linux/-/commit/08da182175db4c7f80850354849d95f2670e8cd9
>>>> FWIW, you in the flood of emails likely missed that this is the same
>>>> thread where you yesterday replied "If the module parameter didn't help
>>>> then perhaps you are seeing some other issue.  Can you bisect?". That's
>>>> why I decided to add this to the tracking. Or am I missing something
>>>> obvious here?
>>>>
>>>> /me looks around again and can't see anything, but that doesn't have to
>>>> mean anything...
>>>>
>>>> Felix, btw, this guide might help you with the bisection, even if it's
>>>> just for kernel compilation:
>>>>
>>>> https://docs.kernel.org/next/admin-guide/quickly-build-trimmed-linux.html
>>>>
>>>> And to indirectly reply to your mail from yesterday[1]. You might want
>>>> to ignore the arch linux kernel git repo and just do a bisection 
>>>> between
>>>> 6.1 and the latest 6.2.y kernel using upstream repos; and if I were you
>>>> I'd also try 6.3 or even mainline before that, in case the issue was
>>>> fixed already.
>>>>
>>>> [1]
>>>> https://lore.kernel.org/all/04749ee4-0728-92fe-bcb0-a7320279eaac@felixrichter.tech/
>>>>
>>> Thanks for the pointers, I'll do a bisection on my desktop from 6.1 to
>>> the newest commit.
>> FWIW, I wonder what you actually mean with "newest commit" here: a
>> bisection between 6.1 and mainline HEAD might be a waste of time, *if*
>> this is something that only happens in 6.2.y (say due to a broken or
>> incomplete backport)
>>
>>> That was the part I was mostly unsure about … where
>>> to start from.
>>>
>>> I was planning to use PKGBUILD scripts from arch to achieve the same
>>> configuration as I would when installing
>>> the package and just rewrite the script to use a local copy of the
>>> source code instead of the repository.
>>> That way I can just use the bisect command, rebuild the package and test
>>> again.
>> In my experience trying to deal with Linux distro's package managers
>> creates more trouble than it's worth.
>>
>>> But I probably won't be able to finish it this week, since I am on
>>> vacation starting tomorrow and will not have access to the computer in
>>> question. I will be back next week, by that time the patch Alex is
>>> talking about might
>>> already be in mainline. So if that fixes it, I will notice and let you
>>> know. If not I will do the bisection to figure out what the actual issue
>>> is.
>> Enjoy your vacation!
>>
>> Ciao, Thorsten
-- 
Hamza