Messages in this thread | | | Date | Fri, 19 Aug 2016 12:02:24 +0530 | From | Vinod Koul <> | Subject | Re: [PATCH] dmaengine: pxa_dma: fix hotchain corner case |
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On Sun, Aug 07, 2016 at 09:01:48PM +0200, Robert Jarzmik wrote: > In the case where a descriptor is chained on a running channel, and as > explained in the comment in the code 10 lines above, the success of the > chaining is ensured either if : > - the DMA is still running > - or if the chained transfer is completed > > Unfortunately the transfer completness test was done on the descriptor > to which the transfer was chained, and not the transfer being chained at > the end, ie. hot-chained. > > This corner case is extremely hard to trigger, as usually the DMA chain > is still running, and the first case takes care of returning success of > the hot-chaining. It was seen by hot-chaining several "small transfers" > to a running "big transfer", not in a real-life usecase but by testing > the robustness of the driver.
Applied, thanks
-- ~Vinod
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