From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olaf Hering Subject: Re: Need help with fixing the Xen waitqueue feature Date: Wed, 23 Nov 2011 19:06:20 +0100 Message-ID: <20111123180620.GA26648@aepfle.de> References: <20111123170017.GC6000@aepfle.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Wed, Nov 23, Keir Fraser wrote: > On 23/11/2011 17:00, "Olaf Hering" wrote: > > > On Tue, Nov 22, Keir Fraser wrote: > > > >> We obviously can't have dom0 going to sleep on paging work. This, at least, > >> isn't a wait-queue bug. > > > > I had to rearrange some code in p2m_mem_paging_populate for my debug > > stuff. This led to an uninitialized req, and as a result req.flags > > sometimes had MEM_EVENT_FLAG_VCPU_PAUSED set. For some reason gcc did > > not catch that.. > > Now waitqueues appear to work ok for me. Thanks! > > Great. However, while eyeballing wait.c I spotted at least two bugs. I'm > pretty sure that the hypervisor will blow up pretty quickly when you resume > testing with multiple physical CPUs, for example. I need to create a couple > of fixup patches which I will then send to you for test. Good, I will look forward for these fixes. > By the way, did you test my patch to domain_crash when the stack-save area > isn't large enough? I ran into the ->esp == 0 case right away, but I need to retest with a clean tree. Olaf