Hi Vinod, On Mon, 29 Apr 2019 at 19:36, Vinod Koul <[email protected]> wrote: > > 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!
Sure, will fix the commit message. > > > 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! No, the descriptor is not completed now. If it is completed, we will return 0 with DMA_COMPLETE status. But now the descriptor is on progress, we should get the descriptor to return current residue. Sorry for confusing description. > > > > > Signed-off-by: Baolin Wang <[email protected]> > > --- > > 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 -- Baolin Wang Best Regards
