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From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 31 Oct 2011 16:34:50 +0100
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Subject: Re: [Qemu-devel] [PATCH] dma: Avoid reentrancy in DMA transfer
	handlers
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To: qemu-devel@nongnu.org

On 10/31/2011 03:46 PM, Kevin Wolf wrote:
> >  Hmm, I think you should set rearm = 1 to ensure the BH is run when
> >  ultimately you leave the sync read.  Sorry for not spotting this before.
>
> I was about to agree, but in fact adding a rearm = 1; line leads to
> crashes, whereas in the version I posted it just works. So it looks like
> something is wrong with doing it, even though it seemed to make perfect
> sense at the first sight.

But what will restart the DMA at the end of the synchronous I/O, then?

Paolo