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Subject: Re: [Qemu-devel] kvm PCI assignment & VFIO ramblings
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To: "Roedel, Joerg" <Joerg.Roedel@amd.com>
Cc: Alex Williamson <alex.williamson@redhat.com>, Alexey Kardashevskiy <aik@au1.ibm.com>, "kvm@vger.kernel.org" <kvm@vger.kernel.org>, Paul Mackerras <pmac@au1.ibm.com>, "linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>, qemu-devel <qemu-devel@nongnu.org>, Alexander Graf <agraf@suse.de>, chrisw <chrisw@sous-sol.org>, iommu <iommu@lists.linux-foundation.org>, linuxppc-dev <linuxppc-dev@lists.ozlabs.org>, "benve@cisco.com" <benve@cisco.com>

On 08/26/2011 12:24 PM, Roedel, Joerg wrote:
> >
> >  As I see it there are two options: (a) make subsequent accesses from
> >  userspace or the guest result in either a SIGBUS that userspace must
> >  either deal with or die, or (b) replace the mapping with a dummy RO
> >  mapping containing 0xff, with any trapped writes emulated as nops.
>
> The biggest problem with this approach is that it has to happen in the
> context of the given process. Linux can't really modify an mm which
> which belong to another context in a safe way.
>

Is use_mm() insufficient?

-- 
error compiling committee.c: too many arguments to function