Prev: rmap: always add new vmas at the end
Next: [PATCH 3/3] jbd2: yield the device queue when waiting for journal commits
From: Alex Williamson on 22 Jun 2010 17:30
On Tue, 2010-06-22 at 15:42 -0400, Konrad Rzeszutek Wilk wrote:
> These nineteen patches lay the groundwork for Xen Paravirtualized (PV)
> domains to access PCI pass-through devices. These patches utilize the
> SWIOTLB library modifications (http://lkml.org/lkml/2010/6/4/272).
>
> The end user of this is the Xen PCI frontend and Xen PCI [1] which
> require a DMA API "backend" that understands Xen's MMU. This allows the
> PV domains to use PCI devices.

Hi Konrad,

Sorry if I missed it, but I didn't see any mention or apparent
requirement of a hardware iommu in xen for this code. Is that true? If
so, is there anything to stop a PV guest with ownership of a DMA capable
PCI device from reading all sorts of memory that the domain wouldn't
otherwise have access to? I was under the impression that the old PCI
front/back for PV guests was mainly an interesting hack with limited
applications due to security. Thanks,

Alex

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
 | 
Pages: 1
Prev: rmap: always add new vmas at the end
Next: [PATCH 3/3] jbd2: yield the device queue when waiting for journal commits