From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alex Williamson <alex.williamson@redhat.com>
Subject: Re: [PATCH V31 10/25] PCI: Lock down BAR access when the kernel is
 locked down
Date: Tue, 26 Mar 2019 15:19:03 -0600
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To: Andy Lutomirski <luto@kernel.org>
Cc: Matthew Garrett <matthewgarrett@google.com>, James Morris <jmorris@namei.org>, LSM List <linux-security-module@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>, David Howells <dhowells@redhat.com>, Linux API <linux-api@vger.kernel.org>, Matthew Garrett <mjg59@srcf.ucam.org>, Matthew Garrett <mjg59@google.com>, Bjorn Helgaas <bhelgaas@google.com>, linux-pci@vger.kernel.org
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On Tue, 26 Mar 2019 13:55:39 -0700
Andy Lutomirski <luto@kernel.org> wrote:

> On Tue, Mar 26, 2019 at 11:28 AM Matthew Garrett
> <matthewgarrett@google.com> wrote:
> >
> > From: Matthew Garrett <mjg59@srcf.ucam.org>
> >
> > Any hardware that can potentially generate DMA has to be locked down in
> > order to avoid it being possible for an attacker to modify kernel code,
> > allowing them to circumvent disabled module loading or module signing.
> > Default to paranoid - in future we can potentially relax this for
> > sufficiently IOMMU-isolated devices.  
> 
> Does this break vfio?

No, vfio provides its own interface to pci config space.  Thanks,

Alex