lkml.org 
[lkml]   [2012]   [Sep]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 05/16] iommu/amd: Split device table initialization into irq and dma part
On Fri, Sep 28, 2012 at 11:00:10AM -0400, Konrad Rzeszutek Wilk wrote:
> On Fri, Sep 28, 2012 at 04:25:55PM +0200, Joerg Roedel wrote:
> > On Fri, Sep 28, 2012 at 10:17:53AM -0400, Konrad Rzeszutek Wilk wrote:
> > > On Fri, Sep 28, 2012 at 02:23:55PM +0200, Joerg Roedel wrote:
> > > > When the IOMMU is enabled very early (as with irq-remapping)
> > > > some devices are still in BIOS hand. When dma is blocked
> > > > early this can cause lots of IO_PAGE_FAULTs. So delay the
> > > > DMA initialization and do it right before the dma_ops are
> > > > initialized.
> > > > To be secure, block all interrupts by default when irq-remapping is
> > >
> > > What are you trying to be secure against?
> >
> > Against attacks of faked MSI msgs that could DoS the system. MSI
> > messages are only specific DMA transactions in the end and a guest with
> > a device assigned has control over its DMA engine and can thus send
> > arbitrary interrupt requests to the host. There is a whole paper about
> > such attacks. I can't find right now, but I send you a link when I find
> > it.
>
> I think I know which one you are talking about - that is the Joanna's
> Rutkowski/Rafal Wojtczuk paper. Could you include a bit about it
> in the description or at least the title in the git commit pls?

Okay, I will do.

--
AMD Operating System Research Center

Advanced Micro Devices GmbH Einsteinring 24 85609 Dornach
General Managers: Alberto Bozzo
Registration: Dornach, Landkr. Muenchen; Registerger. Muenchen, HRB Nr. 43632



\
 
 \ /
  Last update: 2012-09-28 17:41    [W:0.095 / U:0.196 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site