From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [libvirt] [PATCH v2 3/3] KVM: VMX: enable guest access to LMCE related MSRs Date: Mon, 20 Jun 2016 08:55:40 +0200 Message-ID: References: <20160616060531.30028-1-haozhong.zhang@intel.com> <20160616060531.30028-4-haozhong.zhang@intel.com> <1785f481-033b-2780-37b8-d27f80276d33@redhat.com> <20160616145546.GJ18662@thinpad.lan.raisama.net> <20160617011116.7k7e2zmkwhfvajla@hz-desktop> <20160617171515.GJ18662@thinpad.lan.raisama.net> <20160620014951.3kk45qtar7tohj6c@hz-desktop> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Eduardo Habkost , kvm@vger.kernel.org, rkrcmar@redhat.com, Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org, Gleb Natapov , Boris Petkov , Tony Luck , Andi Kleen , Ashok Raj , libvir-list@redhat.com, Jiri Denemark Return-path: In-Reply-To: <20160620014951.3kk45qtar7tohj6c@hz-desktop> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: libvir-list-bounces@redhat.com Errors-To: libvir-list-bounces@redhat.com List-Id: kvm.vger.kernel.org On 20/06/2016 03:49, Haozhong Zhang wrote: > Thanks for the explanation! > > If we disable LMCE in QEMU by default (even for -cpu host), will it > still be a problem? That is, > > - pc-2.7 can continue to run on old kernels unless users explicitly > require LMCE > > - existing libvirt VM configurations can continue to work on pc-2.7 > because LMCE is not specified in those configurations and are > disabled by default (i.e. no requirement for new kernels) > > - existing QEMU configurations/scripts using pc alias can continue to > work on pc-27 for the same reason above. Yes, that would be fine. "-cpu host" can leave LMCE enabled if supported by the kernel. Paolo