Making Composite better for interactive apps

Giuseppe Bilotta giuseppe.bilotta at
Mon Feb 5 00:07:42 UTC 2018

On Mon, Feb 5, 2018 at 12:47 AM, Keith Packard <keithp at> wrote:
> It's interesting to note
> that we could have done the same thing for all of the redirected window
> management requests in the core protocol, simplifying applications
> tremendously...

I'm not sure I follow.

>> The biggest downside I see of this approach is that a CM can stall
>> config changes by keeping a window in the AutoList potentially forever
>> (either because of bugs or maliciously). This is particularly
>> important if any client can do Present requests with an AutoList.
> Well, only one client can be the Compositing Manager with the
> appropriate redirection of all window rendering, so we can probably
> restrict the Auto List to only affect windows that the Compositing
> Manager has redirected.

(Or their descendants). But aside from the restriction on which window
can be in the AutoList, my question was more along the lines of which
clients should be allowed to specify an AutoList at all, and if the
AutoList make senses at all outside of the Present requests from the
Compositing Manager.

> I've a whole separate set of plans for making X more secure; I hope to
> start writing those up in a few months.

Looking forward to give it a read.

Giuseppe "Oblomov" Bilotta

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