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Subject: Re: [PATCH v1 0/1] s390: virtio-ccw: PV needs VIRTIO I/O device
 protection
To:     Cornelia Huck <cohuck@redhat.com>
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        borntraeger@de.ibm.com, frankja@linux.ibm.com, mst@redhat.com,
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From:   Pierre Morel <pmorel@linux.ibm.com>
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Date:   Fri, 7 Aug 2020 16:25:59 +0200
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On 2020-08-06 17:47, Cornelia Huck wrote:
> On Thu,  6 Aug 2020 16:23:01 +0200
...
> This does work, and I'm tempted to queue this patch, but I'm wondering
> whether we need to give up on a cross-architecture solution already
> (especially keeping in mind that ccw is the only transport that is
> really architecture-specific).
> 
> I know that we've gone through a few rounds already, and I'm not sure
> whether we've been there already, but:
> 
> Could virtio_finalize_features() call an optional
> arch_has_restricted_memory_access() function and do the enforcing of
> IOMMU_PLATFORM? That would catch all transports, and things should work
> once an architecture opts in. That direction also shouldn't be a
> problem if virtio is a module.

Yes thanks, I rework it in this direction.


-- 
Pierre Morel
IBM Lab Boeblingen