Commit dbe4c636 authored by Felix Kuehling's avatar Felix Kuehling Committed by Alex Deucher
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drm/amdgpu: Fail DMABUF map of XGMI-accessible memory 



If peer memory is XGMI-accessible, we should never access it through PCIe
P2P DMA mappings. PCIe P2P is slower, has different coherence behaviour,
limited or no support for atomics, or may not work at all. Fail with a
warning if DMABUF mappings of such memory are attempted.

Signed-off-by: default avatarFelix Kuehling <felix.kuehling@amd.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 727b77df

drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c

+5 −0
Original line number Diff line number Diff line
@@ -199,6 +199,11 @@ static struct sg_table *amdgpu_dma_buf_map(struct dma_buf_attachment *attach, 
		break;



	case TTM_PL_VRAM:

		/* XGMI-accessible memory should never be DMA-mapped */

		if (WARN_ON(amdgpu_dmabuf_is_xgmi_accessible(

				dma_buf_attach_adev(attach), bo)))

			return ERR_PTR(-EINVAL);



		r = amdgpu_vram_mgr_alloc_sgt(adev, bo->tbo.resource, 0,

					      bo->tbo.base.size, attach->dev,

					      dir, &sgt);