11.06.2020 11:17, Daniel Stone пишет:
Hi Dmitry,
On Thu, 11 Jun 2020 at 08:54, Dmitry Osipenko digetx@gmail.com wrote:
10.06.2020 14:30, Thierry Reding пишет:
From: Thierry Reding treding@nvidia.com As of commit 4dc55525b095 ("drm: plane: Verify that no or all planes have a zpos property") a warning is emitted if there's a mix of planes with and without a zpos property.
What problem does it solve?
Well, it fixes the WARN_ON, which asserts that either no planes have the zpos property attached, or all planes have the zpos property attached. When only _some_ planes have the property, the property is pretty much useless: zpos exists to guarantee to userspace the relative ordering between planes, defined by the value of the property. If not all planes have the property, then userspace cannot reason about the ordering, since some of the planes have undefined ordering.
Hello Daniel,
So it's a kernel warning, thank you for the clarification! I'm running only older Tegras that have a black-n-white cursor plane, but this is not supported by the upstream kernel. No wonder that I haven't seen the warning, this made me curious what this patch is about :)