Re: [Xen-users] Latest AMD, IOMMU Security Change causing CPU0 Panic and general Problems with AMD+IOMMU changes

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 15.02.13 at 03:55, Matthias <matthias.kannenberg@xxxxxxxxxxxxxx> wrote:
> Unfortunatly, the changes disable my IOMMU rendering pci and vga
> passthrough unusable for me. Now, I might have missed something, but
> what exactly is the point of this at all? My Xen is running fine with
> AMD IOMMU for years now but if i still want to do this, I have to
> revert changes 26532, 26531, 26519, 26518 and 25617 (basically all the
> AMD/IOMMU changes).

No, you rather need to get your firmware fixed, because this

> (XEN) IVHD Error: no information for IO-APIC 0x6

is simply not tolerable. But you can, at the expense of security,
revert to using the global interrupt remapping table, as pointed
out in this same context to others before
("iommu=no-amd-iommu-perdev-intremap").

And yes, we are indeed re-thinking the situation, but in everything
to consider doing you need to realize the security implications. See
for instance
http://lists.xen.org/archives/html/xen-devel/2013-02/msg00591.html
and the single IOMMU consideration in
http://lists.xen.org/archives/html/xen-devel/2013-02/msg00817.html
(but which I don't think will actually work without looking at the PCI
bus topology). Feel free to participate in that discussion.

Jan


_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxx
http://lists.xen.org/xen-users