On 31 August 2018 at 15:38, Michel Dänzer <michel at daenzer.net> wrote: > > [ Adding the amd-gfx list ] > > On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote: >> On 08/31/2018 02:30 PM, Emil Velikov wrote: >>> On 31 August 2018 at 12:54, Thomas Hellstrom <thellstrom at vmware.com> >>> wrote: >>>> To determine whether a device node is a drm device node or not, the code >>>> currently compares the node's major number to the static drm major >>>> device >>>> number. >>>> >>>> This breaks the standalone vmwgfx driver on XWayland dri clients, >>>> >>> Any particular reason why the code doesn't use a fixed node there? >>> It will make the diff vs the in-kernel driver a bit smaller. >> Because then it won't be able to interoperate with other in-tree >> drivers, like virtual drm drivers or passthrough usb drm drivers. >> There is no clean way to share the minor number allocation with in-tree >> drm, so standalone vmwgfx is using dynamic major allocation. > > I wonder why I haven't heard of any of these issues with the standalone > version of amdgpu shipped in packaged AMD releases. Does that also use a > different major number? If yes, maybe it's just that nobody has tried > Xwayland clients with that driver. If no, how does it avoid the other > issues described above? > AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use. -Emil
