On 15-04-19, 20:14, Baolin Wang wrote:
> We will get a NULL virtual descriptor by vchan_find_desc() when the descriptor
> has been submitted, that will crash the kernel when getting the engine status.
No that is wrong, status is for descriptor and not engine!
> In this case, since the descriptor has been submitted, which means the pointer
> 'schan->cur_desc' will point to the current descriptor, then we can use
> 'schan->cur_desc' to get the engine status to avoid this issue.
Nope, since the descriptor is completed, you return with residue as 0
and DMA_COMPLETE status!
>
> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
> ---
> drivers/dma/sprd-dma.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
> index 48431e2..e29342a 100644
> --- a/drivers/dma/sprd-dma.c
> +++ b/drivers/dma/sprd-dma.c
> @@ -625,7 +625,7 @@ static enum dma_status sprd_dma_tx_status(struct dma_chan *chan,
> else
> pos = 0;
> } else if (schan->cur_desc && schan->cur_desc->vd.tx.cookie == cookie) {
> - struct sprd_dma_desc *sdesc = to_sprd_dma_desc(vd);
> + struct sprd_dma_desc *sdesc = schan->cur_desc;
>
> if (sdesc->dir == DMA_DEV_TO_MEM)
> pos = sprd_dma_get_dst_addr(schan);
> --
> 1.7.9.5
--
~Vinod
