Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756691Ab1BJRxr (ORCPT ); Thu, 10 Feb 2011 12:53:47 -0500 Received: from zakopane.cs.ubc.ca ([198.162.52.68]:42718 "EHLO mail.quuxuum.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756679Ab1BJRxq (ORCPT ); Thu, 10 Feb 2011 12:53:46 -0500 Date: Thu, 10 Feb 2011 09:53:44 -0800 From: Brendan Cully To: Ian Campbell Cc: "xen-devel@lists.xensource.com" , LKML , Alan@cs.ubc.ca, "Rafael J. Wysocki" , Stern , "linux-pm@lists.linux-foundation.org" , "SUZUKI, Kazuhiro" Subject: Re: [Xen-devel] Re: [linux-pm] [PATCH 0/2] Fix hangup after creating checkpoint on Xen. Message-ID: <20110210175344.GB380@zanzibar.kublai.com> Mail-Followup-To: Ian Campbell , "xen-devel@lists.xensource.com" , LKML , Alan@cs.ubc.ca, "Rafael J. Wysocki" , Stern , "linux-pm@lists.linux-foundation.org" , "SUZUKI, Kazuhiro" References: <1297186554.9388.248.camel@zakaz.uk.xensource.com> <20110209231659.GB249@zanzibar.kublai.com> <1297337473.20491.144.camel@zakaz.uk.xensource.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1297337473.20491.144.camel@zakaz.uk.xensource.com> X-Operating-System: Darwin 10.6.0 i386 User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1428 Lines: 30 On Thursday, 10 February 2011 at 11:31, Ian Campbell wrote: > On Wed, 2011-02-09 at 23:16 +0000, Brendan Cully wrote: > > I'd like to keep the fast resume option, and expect that it can be > > contained entirely in Xen-specific code. I'll try to get someone to > > look into it here. > > Thanks, please put them in contact with Kazuhiro who has already been > looking into this. > > > I think fast resume is somewhat orthogonal to the problem of hanging > > on resume, which just sounds like a xen-specific bug in the slow > > path. > > The bug on the Xen side is taking the slow path when the suspend was > actually cancelled, which is what the original patch tries to fix. > > Or should/could the slow path be able cope either way? I haven't looked at what's actually happening yet, but what should be happening is that the pvops kernel should not advertise SUSPEND_CANCEL since it doesn't yet support it. So xm save -c should call xc_domain_resume with the fast argument set to 0, to do slow path resumption, and that slow path should be able to handle resuming on the same host where it suspended. Slow path resumption from checkpoint was supported in the pre-pvops kernel. -- 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/