Messages in this thread | | | Date | Fri, 18 Apr 2014 09:50:19 +0100 | From | Russell King - ARM Linux <> | Subject | Re: [PATCH] [FIX] dmaengine: virt-dma: Free descriptor after callback |
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On Thu, Apr 17, 2014 at 07:56:50PM -0500, Joel Fernandes wrote: > Free the vd (virt descriptor) after the callback is called. In EDMA driver > atleast which uses virt-dma, we make use of the desc during the callback and if > its dangerously freed before the callback is called. I also noticed this in > omap-dma dmaengine driver.
You've missed the vital bit of information: why do you make use of the descriptor afterwards? You shouldn't. omap-dma doesn't either.
Once clients submit their request to DMA engine, they must not hold any kind of reference to the descriptor other than the cookie.
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