Re: [PATCH] dmaengine: fix regression introduced by d6103085dfd83c13db65c3bd7e182f021d77c541

From: Dan Williams
Date: Tue Mar 31 2009 - 12:34:00 EST


Guennadi Liakhovetski wrote:
chan is an index variable, used to loop over a list of channels, and here it is used _after_ the loop, in which case it doesn't point to a DMA channel struct anymore. Dereferencing it leads to a corruption of a random memory location, which in my case was a pointer inside a clock struct. Fix it by using a local variable pointing to the DMA device.

Signed-off-by: Guennadi Liakhovetski <lg@xxxxxxx>
---

Guys, this was a _real_ bad joke, cost me almost a day, and that patch has been reviewed by two persons...

<rant>
So far 2.6.29(-next) has been very bad for me, regressions all over the place, lots of wasted time hunting them down:-(
</rant>


Guennadi,

Thanks for testing the 'next' branch and finding this before it hit mainline. I will fold this change into the existing commit with a [lg@xxxxxxx: fix bad usage of 'chan' in dma_async_device_register]

Regards,
Dan
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