From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45312) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bmxAf-0001R1-1a for qemu-devel@nongnu.org; Thu, 22 Sep 2016 02:07:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bmxAe-00055g-2r for qemu-devel@nongnu.org; Thu, 22 Sep 2016 02:07:44 -0400 Message-ID: <1474524441.2857.159.camel@kernel.crashing.org> From: Benjamin Herrenschmidt Date: Thu, 22 Sep 2016 16:07:21 +1000 In-Reply-To: <20160922052105.GD7915@in.ibm.com> References: <20160922052105.GD7915@in.ibm.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] pseries-2.6 migration from QEMU-2.6 to QEMU-2.7 broken List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: bharata@linux.vnet.ibm.com, qemu-devel@nongnu.org, qemu-ppc@nongnu.org Cc: david@gibson.dropbear.id.au, clg@kaod.org, "Nikunj A. Dadhania" On Thu, 2016-09-22 at 10:51 +0530, Bharata B Rao wrote: > The flag values are expected to remain same for a machine version for > the migration to succeed, but this expectation is broken now. Should > we make the addition of these flags conditional on machine type > version ? > But these flags are part of POWER8 CPU definition which is common for > both pseries and upcoming powernv. Does this affect KVM ? (And if yes why on earth would KVM give a flying f*** about the TCG instruction flags ?) ... If not, then I think we can safely not care. This migration business is making life really really really hard ... Ben.