dma_virt_ops is used by virtual devices that map pages / scatterlists to virtual addresses for CPU access instead of performing DMA. This is not the intended use of dma_buf_attach() and dma_buf_map_attachment(). CPU access of dma-buf should use dma_buf_vmap() and related functions. Signed-off-by: Jianxin Xiong <jianxin.xiong@xxxxxxxxx> --- drivers/dma-buf/dma-buf.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 9a054fb5..ba2b877 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -686,6 +686,11 @@ struct dma_buf_attachment * if (WARN_ON(importer_ops && !importer_ops->move_notify)) return ERR_PTR(-EINVAL); +#ifdef CONFIG_DMA_VIRT_OPS + if (dev->dma_ops == &dma_virt_ops) + return ERR_PTR(-EINVAL); +#endif + attach = kzalloc(sizeof(*attach), GFP_KERNEL); if (!attach) return ERR_PTR(-ENOMEM); -- 1.8.3.1