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Date: Fri, 09 Sep 2011 15:43:14 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 3/5] dma-helpers: rewrite
	completion/cancellation
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To: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-devel@nongnu.org

On 09/09/2011 03:34 PM, Kevin Wolf wrote:
> So the release that we avoid is the release in the callback that may or
> may not be called indirectly by bdrv_aio_cancel. We always call
> dma_complete at the end of dma_aio_cancel so that it will be properly freed.
>
>> In fact it may be worse than just the qemu_aio_release: if the driver is
>> waiting for the request to complete, it will write over the bounce
>> buffer after dma_bdrv_unmap has been called.
>
> How that? dma_bdrv_unmap is called only afterwards, isn't it?

I had missed your point completely. :)  Yes, the above should work.

Paolo