From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH 00/18] virtio-blk: Support "VIRTIO_CONFIG_S_NEEDS_RESET"
Date: Mon, 20 Apr 2015 22:34:28 +0200
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Fam Zheng <famz@redhat.com>, qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org, "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>, Stefan Hajnoczi <stefanha@redhat.com>, Amit Shah <amit.shah@redhat.com>
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On Mon, Apr 20, 2015 at 09:10:02PM +0200, Paolo Bonzini wrote:
> 
> 
> On 20/04/2015 19:36, Michael S. Tsirkin wrote:
> > At the implementation level, there's one big issue you seem to have
> > missed: DMA to invalid memory addresses causes a crash in memory core.
> > I'm not sure whether it makes sense to recover from virtio core bugs
> > when we can't recover from device bugs.
> 
> What do you mean exactly?  DMA to invalid memory addresses causes
> address_space_map to return a "short read".
> 
> Paolo

I mean, first of all, a bunch of virtio_XXX_phys calls.
These eventually call qemu_get_ram_ptr, which internally calls
qemu_get_ram_block and ramblock_ptr.
Both abort on errors.

-- 
MST