Plymouth flicker-free shutdown side-effect

[Daniel Drake]

Hi Hans,

Thanks for your input here.

On Thu, Jan 3, 2019 at 10:32 PM Hans de Goede <hdegoede at redhat.com> wrote:
> But there is a proper way to fix this, which is to allow applications to
> unref a framebuffer rather then removing it. In this case the kernel would no
> longer accept the framebuffer handle from userspace (and untie it from the drm fd)
> but keep it around until a new framebuffer is installed. This would also avoid the
> need for the complex stop plymouth, wait for gdm to install new fb, exit plymouth
> shenanigans we need to do atm.
>
> Rob Clark has written a patch for this, but it did not get merged since there were
> no immediate userspace uses for it back when this was first submitted:
>
> https://www.spinics.net/lists/dri-devel/msg140912.html
>
> I believe now would be a good time to dust-off this patch and to teach mutter
> to call the unref ioctl on the last shown framebuffer when it exits, so that
> that stays around until something else installs a new framebuffer.

Just a quick question on this future path. I assume you are referring
to wayland setup here - is mutter actually the component that does
addfb/rmfb in that case?

In our case we are still on X11 so I believe we'd have to modify the X
server here, which sounds painful.

Daniel