Comment 62 for bug 1753776

(In reply to Daniel Stone from comment #15)

> There are exactly three options to fix this:
> a) stop using -background none (I didn't notice this since my DM launches
> a Wayland session, and Xorg is something I only start from a VT without bg
> none); or

I think (a) is worse than doing nothing. At least if we do nothing then a subset of users still have a nice seamless login.

> b) revert the Mesa commit and take a hit from not having renderbuffer
> compression enabled; or

We might do this in the short term for Ubuntu at least. Not having compression enabled is better than us having to deal with recurring bug reports from users about their corrupt screens.

> c) add a GetFB2 ioctl to the kernel + libdrm which includes multi-planar
> and modifier information, use that in Xorg as well as a modifier-aware
> gbm_bo import interface.

Sounds like a good long term solution.

Medium-term there's probably also another option:

  d) Add a small feature to mutter to allow the caller (gdm3) to specify that only simple (linear?) formats are allowed, so as to enable easy transitions for all display server types. gdm3 probably cares less about the benefits of compression than gnome-shell-proper does.