Messages in this thread | | | Date | Tue, 22 Mar 2011 11:44:26 +0100 | From | "Roedel, Joerg" <> | Subject | Re: [PATCH 0/6] get rid of on-stack dma buffers |
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On Mon, Mar 21, 2011 at 05:03:15PM -0400, Florian Mickler wrote: > I guess (not verified), that the dma api takes sufficient precautions > to abort the dma transfer if a timeout happens. So freeing _should_ > not be an issue. (At least, I would expect big fat warnings everywhere > if that were the case)
Freeing is very well an issue. All you can expect from the DMA-API is to give you a valid DMA handle for your device. But it can not prevent that a device uses this handle after you returned it. You need to make sure yourself that any pending DMA is canceled before calling kfree().
Joerg
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