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

[Hans de Goede]

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