Re: [PATCH 0/6] get rid of on-stack dma buffers

From: Roedel, Joerg
Date: Tue Mar 22 2011 - 06:44:43 EST

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().


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