Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935134Ab3DIR40 (ORCPT ); Tue, 9 Apr 2013 13:56:26 -0400 Received: from e8.ny.us.ibm.com ([32.97.182.138]:37826 "EHLO e8.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751315Ab3DIR4Y (ORCPT ); Tue, 9 Apr 2013 13:56:24 -0400 Message-ID: <51645630.3030608@linux.vnet.ibm.com> Date: Tue, 09 Apr 2013 13:56:00 -0400 From: "Michael R. Hines" User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130106 Thunderbird/17.0.2 MIME-Version: 1.0 To: "Michael S. Tsirkin" CC: Roland Dreier , qemu-devel@nongnu.org, "linux-rdma@vger.kernel.org" , Yishai Hadas , LKML , Hal Rosenstock , Jason Gunthorpe , Sean Hefty , Christoph Lameter Subject: Re: [PATCHv2] rdma: add a new IB_ACCESS_GIFT flag References: <20130324155153.GA8597@redhat.com> <515F3160.4020007@linux.vnet.ibm.com> <515F3A0F.5030507@linux.vnet.ibm.com> <20130409163929.GA7661@redhat.com> In-Reply-To: <20130409163929.GA7661@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13040917-9360-0000-0000-000011AA0797 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1226 Lines: 32 On 04/09/2013 12:39 PM, Michael S. Tsirkin wrote: > On Fri, Apr 05, 2013 at 04:54:39PM -0400, Michael R. Hines wrote: >> To be more specific, here's what I did: >> >> 1. apply kernel module patch - re-insert module >> 1. QEMU does: ibv_reg_mr(........IBV_ACCESS_GIFT | IBV_ACCESS_REMOTE_READ) >> 2. Start the RDMA migration >> 3. Migration completes without any errors >> >> This test does *not* work with a cgroup swap limit, however. The >> process gets killed. (Both with and without GIFT) >> >> - Michael > Try to attach a debugger and see where it is when it gets killed? > It's killed by cgroups - not a CPU exception. The same test works fine using TCP migration with cgroups - everything is fine there. The memory that RDMA attempted to register hits some kind of cgroups policy which results in a kernel message saying that the cgroup swap limit was hit and then it goes ahead and kills the process altogether. It's not a QEMU problem - it seems to be a kernel bug. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/