Status of mainline guest drivers

[atler]

Now that vboxsf is mainlined too I've decided to take another try at drivers for VirtualBox Linux guest shipped with kernel. While shared folders appear to work fine, with manual work to avoid using mount.vboxsf though, vboxguest is still not functional: resizing with VMSVGA display does not work (didn't try other displays) as apparently mainline lacks support for VMMDevReq_GetDisplayChangeRequestMulti. When invoking VBoxClient --vmsvga dmesg shows:

Denying userspace vmm call type 0x000051

So what is exact plan regarding mainline drivers? Will they ultimately replace drivers shipped with VirtualBox? Is there a plan to get them up-to-date?