amdgpu_ttm_tt_unpopulate can be called during bo_destroy. The dmabuf->resv must not be held by the caller or dma_buf_detach will deadlock. This is probably not the right fix. I get a recursive lock warning with the reservation held in ttm_bo_release. Should unmap_attachment move to backend_unbind instead?
Signed-off-by: Felix Kuehling Felix.Kuehling@amd.com --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 936b3cfdde55..257750921eed 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -1216,9 +1216,22 @@ static void amdgpu_ttm_tt_unpopulate(struct ttm_device *bdev,
if (ttm->sg && gtt->gobj->import_attach) { struct dma_buf_attachment *attach; + bool locked;
attach = gtt->gobj->import_attach; + /* FIXME: unpopulate can be called during bo_destroy. + * The dmabuf->resv must not be held by the caller or + * dma_buf_detach will deadlock. This is probably not + * the right fix. I get a recursive lock warning with the + * reservation held in ttm_bo_releas.. Should + * unmap_attachment move to backend_unbind instead? + */ + locked = dma_resv_is_locked(attach->dmabuf->resv); + if (!locked) + dma_resv_lock(attach->dmabuf->resv, NULL); dma_buf_unmap_attachment(attach, ttm->sg, DMA_BIDIRECTIONAL); + if (!locked) + dma_resv_unlock(attach->dmabuf->resv); ttm->sg = NULL; return; }