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Date: Wed, 19 Sep 2012 06:32:57 +0200
From: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
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Subject: Re: [Qemu-devel] [PATCH V3 10/11] vcpu: introduce lockmap
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To: Peter Crosthwaite <peter.crosthwaite@petalogix.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, Igor Mitsyanko <i.mitsyanko@samsung.com>, Jan Kiszka <jan.kiszka@siemens.com>, Marcelo Tosatti <mtosatti@redhat.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, liu ping fan <qemulist@gmail.com>, Avi Kivity <avi@redhat.com>, Anthony Liguori <anthony@codemonkey.ws>, Paolo Bonzini <pbonzini@redhat.com>

On Wed, Sep 19, 2012 at 02:25:48PM +1000, Peter Crosthwaite wrote:
> Ping for PMM,
> 
> This is the root case of your block on the SDHCI series - this is a
> discussion on resolution to bogus infinite looping DMA. For current
> participants in this discussion, heres our thread on the same topic
> over in SD land:
> 
> http://lists.gnu.org/archive/html/qemu-devel/2012-08/msg01017.html
> 
> With the findings here and acknowledgement that this is a general
> problem, we either need to declare this issue of scope for SDHCI, or
> work with these guys (in the immediate future) on the DMA infinite
> loop problem flagged here. I dont mind if SDHCI+ADMA is the guinea pig
> here, but can we get a decisive plan for going forward with this issue
> if it is going to continue to block SDHCI.
> 
> Thanks to Igor for identifying the overlap between these discussions.

Hi,

A couple of dumb questions.

What is the reason for the blocker? that possible guest dos is worse
than no functionality at all?

Can't you put the DMA/IO processing into the background?

what's the diff between setup of bad descriptors and  writing a
while (1) loop in the guest CPU?

Cheers,
E