Re: [PATCH V4 0/6] perf/amd/iommu: Enable multi-IOMMU support

[Suravee Suthikulpanit]

Hi,

On 02/23/2016 06:04 PM, Joerg Roedel wrote:
> Hi Suravee,
>
> On Thu, Feb 11, 2016 at 04:15:21PM +0700, Suthikulpanit, Suravee wrote:
> > From: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
> >
> > This patch series modifies the existing perf_event_amd_iommu driver
> > to support systems with multiple IOMMUs. It introduces new AMD IOMMU APIs,
> > which are used by the AMD IOMMU Perf driver to access performance
> > counters in multiple IOMMUs.
> >
> > In addition, this series should also fix current AMD IOMMU PMU driver
> > initialization issue in some existing KV and CZ platform, where it fails
> > to write to IOMMU perf counter as reported by Andreas Hartmann here
> > (http://comments.gmane.org/gmane.linux.kernel.pci/49147).
>
> Since that problem also affects older kernels, we need a stand-alone
> fix for this initialization issue. We can't backport new features to fix
> bugs in old kernels.
>
>
> 	Joerg

OK, I am spliting V5 into two part. First would be just to fix the 
issue. Then the second part would be to add the multiple IOMMU support.

Suravee