[Intel-gfx] [5.18 regression] drm/i915 BYT rendering broken due to "Remove short-term pins from execbuf, v6" #forregzbot

[Thorsten Leemhuis]

TWIMC: this mail is primarily send for documentation purposes and for
regzbot, my Linux kernel regression tracking bot. These mails usually
contain '#forregzbot' in the subject, to make them easy to spot and filter.

On 09.05.22 09:01, Thorsten Leemhuis wrote:
> [TLDR: I'm adding this regression report to the list of tracked
> regressions; all text from me you find below is based on a few templates
> paragraphs you might have encountered already already in similar form.]
> 
> Hi, this is your Linux kernel regression tracker. Top-posting for once,
> to make this easily accessible to everyone.
> 
> Thanks for the report.
> 
> To be sure below issue doesn't fall through the cracks unnoticed, I'm
> adding it to regzbot, my Linux kernel regression tracking bot:
> 
> #regzbot ^introduced b5cfe6f7a6e1
> #regzbot title drm/i915: BYT rendering broken due to "Remove short-term
> pins from execbuf, v6"
> #regzbot ignore-activity

#regzbot link: https://gitlab.freedesktop.org/drm/intel/-/issues/5806
#regzbot monitor:
https://lore.kernel.org/all/20220511115219.46507-1-maarten.lankhorst@linux.intel.com/

> 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 -- ideally with also
> telling regzbot about it, as explained here:
> https://linux-regtracking.leemhuis.info/tracked-regression/
> 
> Reminder for developers: When fixing the issue, add 'Link:' tags
> pointing to the report (the mail this one replied to), as the kernel's
> documentation call for; above page explains why this is important for
> tracked regressions.
> 
> Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
> 
> P.S.: As the Linux kernel's regression tracker I deal with a lot of
> reports and sometimes miss something important when writing mails like
> this. If that's the case here, don't hesitate to tell me in a public
> reply, it's in everyone's interest to set the public record straight.
> 
> 
> 
> On 08.05.22 16:38, Hans de Goede wrote:
>> Hi All,
>>
>> When running a 5.18-rc4 (and -rc5) kernel on a Chuwi Hi 8, which is
>> a Bay Trail based tablet with 2G RAM and a 1200x1920 DSI panel.
>> I noticed that gnome-shell was misrendering. Many UI elements were
>> missing (they were all black) and at the gdm login screen (which is
>> a special gnome-shell session) the screen often was entirely black
>> until I move the cursor around and then various things got
>> highlighted after which they sometimes stuck around and sometimes
>> they disappeared again after the highlight.
>>
>> Since this problem does not happen with various 5.17.y kernels I
>> believe that this is a kernel regression in 5.18. I've bisected this
>> and the bisect points to:
>>
>> commit b5cfe6f7a6e1 ("drm/i915: Remove short-term pins from execbuf, v6.")
>>
>> from Maarten. This commit cleanly reverts on top of 5.18-rc5 and
>> I can confirm that 5.18-rc5 with b5cfe6f7a6e1 reverted fixes things.
>>
>> I would be more then happy to test any possible fixes for this.
>>
>> Regards,
>>
>> Hans
>>
>>
>>