From 9397204ffae887bd557e7053609174b3eb9d6f5c Mon Sep 17 00:00:00 2001 From: Felix Kuehling Date: Thu, 17 Apr 2025 12:02:09 -0400 Subject: [PATCH 3442/5403] drm/amdgpu: Fail DMABUF map of XGMI-accessible memory MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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: Felix Kuehling Reviewed-by: Christian König Signed-off-by: Alex Deucher (cherry picked from commit dbe4c63689bc6b5fd3ab72650ea4b6a667e96a68) --- drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c index e6913fcf2c7b..44e120f9f764 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c @@ -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); -- 2.54.0