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

[Thorsten Leemhuis]

[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

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
> 
> 
>