From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: kvm PCI assignment & VFIO ramblings
Date: Sun, 28 Aug 2011 16:14:00 +0300
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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>
To: "Roedel, Joerg" <Joerg.Roedel@amd.com>
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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