From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754584AbbIHNhq (ORCPT ); Tue, 8 Sep 2015 09:37:46 -0400 Received: from e28smtp06.in.ibm.com ([122.248.162.6]:34856 "EHLO e28smtp06.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752702AbbIHNhn (ORCPT ); Tue, 8 Sep 2015 09:37:43 -0400 X-Helo: d28dlp03.in.ibm.com X-MailFrom: bharata@linux.vnet.ibm.com X-RcptTo: linux-kernel@vger.kernel.org Date: Tue, 8 Sep 2015 19:07:15 +0530 From: Bharata B Rao To: "Dr. David Alan Gilbert" Cc: Michael Ellerman , Andrea Arcangeli , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, qemu-devel@nongnu.org, kvm@vger.kernel.org, linux-api@vger.kernel.org, zhang.zhanghailiang@huawei.com, Pavel Emelyanov , Johannes Weiner , Hugh Dickins , Sanidhya Kashyap , Dave Hansen , Andres Lagar-Cavilla , Mel Gorman , Paolo Bonzini , "Kirill A. Shutemov" , "Huangpeng (Peter)" , Andy Lutomirski , Linus Torvalds , Peter Feiner , linuxppc-dev@lists.ozlabs.org Subject: Re: [Qemu-devel] [PATCH 19/23] userfaultfd: activate syscall Message-ID: <20150908133647.GA17433@in.ibm.com> Reply-To: bharata@linux.vnet.ibm.com References: <1431624680-20153-1-git-send-email-aarcange@redhat.com> <1431624680-20153-20-git-send-email-aarcange@redhat.com> <20150811100728.GB4587@in.ibm.com> <20150811134826.GI4520@redhat.com> <20150812052346.GC4587@in.ibm.com> <1441692486.14597.17.camel@ellerman.id.au> <20150908063948.GB678@in.ibm.com> <20150908085946.GC2246@work-vm> <20150908095915.GC678@in.ibm.com> <20150908124652.GK2246@work-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150908124652.GK2246@work-vm> User-Agent: Mutt/1.5.23 (2014-03-12) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15090813-0021-0000-0000-0000074294B0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 08, 2015 at 01:46:52PM +0100, Dr. David Alan Gilbert wrote: > * Bharata B Rao (bharata@linux.vnet.ibm.com) wrote: > > On Tue, Sep 08, 2015 at 09:59:47AM +0100, Dr. David Alan Gilbert wrote: > > > * Bharata B Rao (bharata@linux.vnet.ibm.com) wrote: > > > > In fact I had successfully done postcopy migration of sPAPR guest with > > > > this setup. > > > > > > Interesting - I'd not got that far myself on power; I was hitting a problem > > > loading htab ( htab_load() bad index 2113929216 (14848+0 entries) in htab stream (htab_shift=25) ) > > > > > > Did you have to make any changes to the qemu code to get that happy? > > > > I should have mentioned that I tried only QEMU driven migration within > > the same host using wp3-postcopy branch of your tree. I don't see the > > above issue. > > > > (qemu) info migrate > > capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off x-postcopy-ram: on > > Migration status: completed > > total time: 39432 milliseconds > > downtime: 162 milliseconds > > setup: 14 milliseconds > > transferred ram: 1297209 kbytes > > throughput: 270.72 mbps > > remaining ram: 0 kbytes > > total ram: 4194560 kbytes > > duplicate: 734015 pages > > skipped: 0 pages > > normal: 318469 pages > > normal bytes: 1273876 kbytes > > dirty sync count: 4 > > > > I will try migration between different hosts soon and check. > > I hit that on the same host; are you sure you've switched into postcopy mode; > i.e. issued a migrate_start_postcopy before the end of migration? Sorry I was following your discussion with Li in this thread https://www.marc.info/?l=qemu-devel&m=143035620026744&w=4 and it wasn't obvious to me that anything apart from turning on the x-postcopy-ram capability was required :( So I do see the problem now. At the source ------------- Error reading data from KVM HTAB fd: Bad file descriptor Segmentation fault At the target ------------- htab_load() bad index 2113929216 (14336+0 entries) in htab stream (htab_shift=25) qemu-system-ppc64: error while loading state section id 56(spapr/htab) qemu-system-ppc64: postcopy_ram_listen_thread: loadvm failed: -22 qemu-system-ppc64: VQ 0 size 0x100 Guest index 0x0 inconsistent with Host index 0x1f: delta 0xffe1 qemu-system-ppc64: error while loading state for instance 0x0 of device 'pci@800000020000000:00.0/virtio-net' *** Error in `./ppc64-softmmu/qemu-system-ppc64': corrupted double-linked list: 0x00000100241234a0 *** ======= Backtrace: ========= /lib64/power8/libc.so.6Segmentation fault