From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [RFC] Unify KVM kernel-space and user-space code into a single project Date: Wed, 24 Mar 2010 17:03:42 +0100 Message-ID: <1269446622.5109.388.camel@twins> References: <20100323140608.GJ1940@8bytes.org> <4BA8EEDE.8070309@redhat.com> <20100323182153.GA14800@8bytes.org> <4BA99BCB.5080501@redhat.com> <20100324115900.GB14800@8bytes.org> <4BAA00B1.20407@redhat.com> <20100324125043.GC14800@8bytes.org> <4BAA0DFE.1080700@redhat.com> <20100324134642.GD14800@8bytes.org> <4BAA1A53.20207@redhat.com> <20100324150137.GE14800@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Cc: Avi Kivity , Anthony Liguori , Ingo Molnar , Pekka Enberg , "Zhang, Yanmin" , Sheng Yang , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Marcelo Tosatti , Jes Sorensen , Gleb Natapov , ziteng.huang@intel.com, Arnaldo Carvalho de Melo , Fr?d?ric Weisbecker , Gregory Haskins To: Joerg Roedel Return-path: In-Reply-To: <20100324150137.GE14800@8bytes.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Wed, 2010-03-24 at 16:01 +0100, Joerg Roedel wrote: > What I meant was: perf-kernel puts the guest-name into every sample and > perf-userspace accesses /sys/kvm/guest_name/fs/ later to resolve the > symbols. I leave the question of how the guest-fs is exposed to the host > out of this discussion. We should discuss this seperatly. I'd much prefer a pid like suggested later, keeps the samples smaller. But that said, we need guest kernel events like mmap and context switches too, otherwise we simply can't make sense of guest userspace addresses, we need to know the guest address space layout. So aside from a filesystem content, we first need mmap and context switch events to find the files we need to access. And while I appreciate all the security talk, its basically pointless anyway, the host can access it anyway, everybody agrees on that, but still you're arguing the case..