From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60748) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zqeue-0004ck-4O for qemu-devel@nongnu.org; Mon, 26 Oct 2015 06:22:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZqeuZ-0002kx-LD for qemu-devel@nongnu.org; Mon, 26 Oct 2015 06:22:00 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35160) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZqeuZ-0002kt-FN for qemu-devel@nongnu.org; Mon, 26 Oct 2015 06:21:55 -0400 Date: Mon, 26 Oct 2015 12:21:52 +0200 From: "Michael S. Tsirkin" Message-ID: <20151026122003-mutt-send-email-mst@redhat.com> References: <1445846438-7324-1-git-send-email-bharata@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1445846438-7324-1-git-send-email-bharata@linux.vnet.ibm.com> Subject: Re: [Qemu-devel] [PATCH v2 0/2] Enforce gaps between DIMMs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Bharata B Rao Cc: imammedo@redhat.com, qemu-devel@nongnu.org, david@gibson.dropbear.id.au On Mon, Oct 26, 2015 at 01:30:36PM +0530, Bharata B Rao wrote: > The suggested way to work around the virtio bug reported here > > http://lists.nongnu.org/archive/html/qemu-devel/2015-08/msg00522.html > > is to introduce gaps between DIMMs. Igor's patchset changes the pc-dimm > auto-address assignment to introduce gaps and ues the same from pc memhp. > This patchset does the same for sPAPR PowerPC. > > Before introducing the gap, ensure that memory hotplug region has enough > room for alignment adjustment. We accommodate a max alignment of 256MB for > each slot since sPAPR memory hotplug enforces an alignment requirement of > 256MB on RAM size, maxmem and NUMA node mem sizes. > > This applies on David's spapr-next branch. This is already creating problems on x86. Instead of propagating this all over the place, let's fix things properly to either - handle requests that cross the DIMMs or - make sure guest physically contigious implies host virtually contigious > Changes in v2 > ------------- > - Minor rewording of patch description and code comment in 1/2. > > v1: http://lists.nongnu.org/archive/html/qemu-devel/2015-10/msg02414.html > v0: https://lists.gnu.org/archive/html/qemu-devel/2015-10/msg00749.html > > Bharata B Rao (2): > spapr: Accommadate alignment gaps in hotplug memory region > spapr: Force gaps between DIMM's GPA > > hw/ppc/spapr.c | 23 ++++++++++++++++++----- > 1 file changed, 18 insertions(+), 5 deletions(-) > > -- > 2.1.0