10:39 bjorn3_gh: is this channel only for Xorg or can I ask questions about the kernel mode setting uapi here too? if this is only for Xorg where can I ask about KMS?
10:50 emersion: bjorn3_gh: xserver uses a different channel, this one is for Mesa and KMS
11:32 bjorn3_gh: i'm trying to figure out what the intended semantics of kms framebuffers are with respect to lifetimes and permissions. i can't find any clear docs for this, just fragments in the kernel docs.
11:34 bjorn3_gh: so far i've experimentally found that CLOSEFB will prevent a framebuffer from being assigned to a plane, while still allowing access to it using DRM_IOCTL_MODE_GETFB for as long as there is a plane referencing it. and DRM_IOCTL_MODE_CURSOR creates a framebuffer that behaves similar to one on which CLOSEFB is called.
11:37 bjorn3_gh: i can't find any docs about when clients are supposed to be allowed to access framebuffers created by another client.
12:11 mahkoh: Destroying a framebuffer detaches it from the plan and disables the CRTC it is attached to.
12:11 mahkoh: *plane
12:20 bjorn3_gh: RMFB having that behavior is properly documented. and CLOSEFB is documented as not detaching from planes. i experimentally found that CLOSEFB still allows access through GETFB while it is still attached to some plane, but does not allow attaching it to a plane anymore.
12:22 bjorn3_gh: i'm mostly trying to figure out when you are allowed to access a framebuffer of another client.