From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39666) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aliAL-00052L-Nu for qemu-devel@nongnu.org; Thu, 31 Mar 2016 15:22:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aliAH-0002n6-R8 for qemu-devel@nongnu.org; Thu, 31 Mar 2016 15:22:01 -0400 Received: from mx-v6.kamp.de ([2a02:248:0:51::16]:34522 helo=mx01.kamp.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aliAH-0002me-Ht for qemu-devel@nongnu.org; Thu, 31 Mar 2016 15:21:57 -0400 Message-ID: <56FD78CF.4080201@kamp.de> Date: Thu, 31 Mar 2016 21:21:51 +0200 From: Peter Lieven MIME-Version: 1.0 References: <1459371583-4824-1-git-send-email-pbonzini@redhat.com> <56FD1E68.5020604@redhat.com> <56FD2233.1050708@kamp.de> <56FD24B9.5070601@redhat.com> <6DB6C7C1-2FDB-4478-A2EA-5A71CC3A47A3@kamp.de> <56FD55BB.2010903@redhat.com> In-Reply-To: <56FD55BB.2010903@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [Qemu-stable] [PATCH] target-i386: do not read/write MSR_TSC_AUX from KVM if CPUID bit is not set List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: qemu-stable@nongnu.org, Laszlo Ersek , qemu-devel@nongnu.org, ehabkost@redhat.com Am 31.03.2016 um 18:52 schrieb Paolo Bonzini: > > On 31/03/2016 17:38, Peter Lieven wrote: >> >>> Am 31.03.2016 um 15:23 schrieb Paolo Bonzini : >>> >>> >>> >>>> On 31/03/2016 15:12, Peter Lieven wrote: >>>>>> KVM does not let you read or write this MSR if the corresponding CPUID >>>>>> bit is not set. This in turn causes MSRs that come after MSR_TSC_AUX >>>>>> to be ignored by KVM_SET_MRSS. >>>> Is it possible that this causes a freeze when migrating vom qemu 2.2.0 >>>> to 2.5.1? >>> I wouldn't exclude it if the CPU model is Westmere or earlier. >> the Host CPU or the Emulated CPU? > The guest. I can confirm this seems to fix the migration for emulated Westmere CPUs. Regardless if its a 2.2.0 -> 2.5.1 or 2.5.1 -> 2.5.1 migration. Peter