On Wed, 2 Sep 2020 at 13:49, Simon Ser <contact@xxxxxxxxxxx> wrote: > On Wednesday, September 2, 2020 2:44 PM, Daniel Vetter <daniel.vetter@xxxxxxxx> wrote: > > I don't think that happens, but it has come up in discussions. It's > > kinda different scenario though: getfb2 is for cross-compositor stuff, > > enabling smooth transitions at boot-up and when switching. So you have > > a legit reason for mixing modifier-aware userspace with > > non-modifier-aware userspace. And the modifier-aware userspace would > > like that everything works with modifiers consistently, including > > getfb2. But gbm is just within a single process, and that should > > either run all with modifiers, or not at all, since these worlds just > > dont mix well. Hence I'm not seeing much use for that, -modesetting > > being a confused mess nonwithstanding :-) > > Well… There's also the case where some legacy Wayland client talks to a > modifier-aware compositor. gbm_bo_import would be called without a > modifier, but the compositor expects gbm_bo_get_modifier to work. > > Also, wlroots will call gbm_bo_create without a modifier to only let > the driver pick "safe" modifiers in case passing the full list of > modifiers results in a black screen. Later on wlroots will call > gbm_bo_get_modifier to figure out what modifier the driver picked. I think those are reasonable expectations to have, even though arguably for consistency we should always have a fixed INVALID for when a modifier isn't used. Anyway, patch is: Acked-by: Daniel Stone <daniels@xxxxxxxxxxxxx> Thanks for typing this up! Cheers, Daniel _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
