On Fri, Oct 25, 2024 at 4:36 PM Michel Dänzer <michel.daen...@mailbox.org> wrote:
> On 2024-10-25 12:18, Bas Nieuwenhuizen wrote: > > On Fri, Oct 25, 2024 at 11:21 AM Michel Dänzer < > michel.daen...@mailbox.org <mailto:michel.daen...@mailbox.org>> wrote: > > > > On 2024-10-24 17:08, Marek Olšák wrote: > > > We don't need to share the same VMID between ROCm and Mesa. We > don't > > > need to share the same driver FD between ROCm and Mesa either. It > will > > > be like having 2 different processes, and that should always work. > > > > Per > https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31756#note_2626236 > < > https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31756#note_2626236>, > does anything prevent the application from passing the same DRM file > description (doesn't need to be the same *descriptor*) to separate drivers? > (Not sure it can even pass a DRM fd to ROCm, surely can e.g. to radeonsi & > AMDVLK though) > > > > > > In RADV the app has no way to pass in a drm fd, there is only a way to > query the major/minor from the fd ( > https://registry.khronos.org/vulkan/specs/1.3-extensions/html/chap55.html#VK_EXT_physical_device_drm > < > https://registry.khronos.org/vulkan/specs/1.3-extensions/html/chap55.html#VK_EXT_physical_device_drm > >). > > Hmm. So Wayland compositors which use Vulkan have to share BOs from Vulkan > into their DRM file description for KMS via dma-buf? > > > How about ROCm, no way to pass in / retrieve a DRM file descriptor there > either? > > > > (not to mention that it would mean that any users would need to use > libdrm_amdgpu. Given that the most likely combination of GBM with shared > fd/handle stuff is kernel modesetting and nobody uses libdrm_amdgpu with > that, having a shared libdrm_amdgpu would not help there) > > Not sure what you mean here, Wayland compositors use radeonsi with KMS. > > That is what I mean, since they use KMS directly, anything that radeonsi does wrt using or not using libdrm_amdgpu doesn't impact them. (note that some compositors, like gamescope do the actual dmabuf dance) > > -- > Earthling Michel Dänzer \ GNOME / Xwayland / Mesa developer > https://redhat.com \ Libre software enthusiast >
