From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751949AbcBWLEK (ORCPT ); Tue, 23 Feb 2016 06:04:10 -0500 Received: from 8bytes.org ([81.169.241.247]:33654 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750914AbcBWLEI (ORCPT ); Tue, 23 Feb 2016 06:04:08 -0500 Date: Tue, 23 Feb 2016 12:04:06 +0100 From: Joerg Roedel To: Suravee Suthikulpanit Cc: bp@alien8.de, peterz@infradead.org, mingo@redhat.com, acme@kernel.org, andihartmann@freenet.de, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Subject: Re: [PATCH V4 0/6] perf/amd/iommu: Enable multi-IOMMU support Message-ID: <20160223110406.GA22747@8bytes.org> References: <1455182127-17551-1-git-send-email-Suravee.Suthikulpanit@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1455182127-17551-1-git-send-email-Suravee.Suthikulpanit@amd.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Suravee, On Thu, Feb 11, 2016 at 04:15:21PM +0700, Suthikulpanit, Suravee wrote: > From: Suravee Suthikulpanit > > 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