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Date: Thu, 9 Mar 2017 12:38:23 +0100
From: Cornelia Huck <cornelia.huck@de.ibm.com>
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Subject: Re: [Qemu-devel] [PATCH] virtio: destroy region cache during reset
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>, qemu-devel@nongnu.org, peterx@redhat.com, mst@redhat.com

On Thu, 9 Mar 2017 12:12:00 +0100
Paolo Bonzini <pbonzini@redhat.com> wrote:

> On 09/03/2017 12:07, Cornelia Huck wrote:
> >>> - Driver #2 uses the device without doing a reset or proper setup
> >> Without this patch, even if driver #2 do a reset, it can still use the 
> >> old map if it don't set queue pfn.
> > 
> > Yes, the cleanup-on-reset is definetly needed.
> 
> It is good to have for defensiveness, but it would still cause a
> segfault so we should also add the checks on vq->vring.desc throughout.

Agreed.