On 08/31/2018 04:49 PM, Michel Dänzer wrote: > On 2018-08-31 4:46 p.m., Thomas Hellstrom wrote: >> On 08/31/2018 04:38 PM, Michel Dänzer 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? >>> >>> >> Is standalone AMD supposed to be able to coexist with in-tree drm drivers? > Yes, it does, it's working e.g. on laptops with an Intel integrated and > an AMD discrete GPU. > > Hmm. The symptoms with xf86-video-vmware are that when mesa initializes, we get: MESA-LOADER: failed to retrieve device information MESA-LOADER: failed to retrieve device information MESA-LOADER: failed to retrieve device information but then vmwgfx_dri.so loads anyway. With XWayland, mesa just silently tries swrast instead of vmwgfx. Not sure this has always been the case though. It might be due to a recent XWayland change. In any case, the change to libdrm silence the warnings on Xorg and makes mesa try vmwgfx on XWayland. /Thomas
