From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37262) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bmwRk-0001r0-G5 for qemu-devel@nongnu.org; Thu, 22 Sep 2016 01:21:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bmwRg-0007kb-CB for qemu-devel@nongnu.org; Thu, 22 Sep 2016 01:21:19 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:43473) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bmwRg-0007jq-3l for qemu-devel@nongnu.org; Thu, 22 Sep 2016 01:21:16 -0400 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u8M5IIn9103061 for ; Thu, 22 Sep 2016 01:21:14 -0400 Received: from e23smtp04.au.ibm.com (e23smtp04.au.ibm.com [202.81.31.146]) by mx0a-001b2d01.pphosted.com with ESMTP id 25ktaafb07-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 22 Sep 2016 01:21:14 -0400 Received: from localhost by e23smtp04.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 22 Sep 2016 15:21:12 +1000 Date: Thu, 22 Sep 2016 10:51:05 +0530 From: Bharata B Rao Reply-To: bharata@linux.vnet.ibm.com MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Message-Id: <20160922052105.GD7915@in.ibm.com> Subject: [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: qemu-devel@nongnu.org, qemu-ppc@nongnu.org Cc: david@gibson.dropbear.id.au, benh@kernel.crashing.org, clg@kaod.org, "Nikunj A. Dadhania" Hi, Nikunj and I realized that migrating pseries-2.6 guest from QEMU-2.6 to newer QEMU-2.7 is broken like this: qemu-system-ppc64: error while loading state for instance 0x0 of device 'cpu' qemu-system-ppc64: load of migration failed: Invalid argument Bisecting tells us that 4e0806110c8b896ceff3490f15a616e8b3165efe (ppc: Add PPC_64H instruction flag to POWER7 and POWER8) is the first bad commit. Along with this there are other 3 similar commits which add new bits to insns_flags and insns_flags2 fields of POWER7 and POWER8 CPUs. 4e0806110c8b896ceff3490f15a616e8b3165efe Adds PPC_64H to POWER7 and POWER8 dfdd3e43620a6cd4f2be31da5a257c84a16fc000 Adds PPC_64BX to POWER7 b781537560e3b968b6fe1395e3d07bd67f0009ba Adds PPC_CILDST to POWER7 and POWER8 7778a575c7055276afdd01737e9d1029a65f923d Adds PPC2_PM_ISA206 to POWER7 and POWER8 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. Regards, Bharata.