From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Vrabel Subject: Re: [PATCH 1/2] Revert "xen: properly account for _PAGE_NUMA during xen pte translations" Date: Tue, 25 Mar 2014 19:12:25 +0000 Message-ID: <5331D519.3040505@citrix.com> References: <5331B94F.9020601@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: David Sutton Cc: "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org On 25/03/14 19:03, David Sutton wrote: > David, > > On Tue, Mar 25, 2014 at 12:13 PM, David Vrabel > wrote: > > On 25/03/14 15:28, David Sutton wrote: > > David, > > > >> This reverts commit a9c8e4beeeb64c22b84c803747487857fe424b68. > >> > > Please note: this particular patch also helped to resolve an issue > > reported by some of the people using the xen package under Arch Linux, > > where they would see stability issues running certain software > > (particularly firefox) under dom0 - the software would start crashing > > under relatively light usage, with a kernel BUG message. > > We are aware that Xen PV guests will not work if CONFIG_NUMA_BALANCING > is enabled with this revert. But that patch introduced fundamental > breakage to how a guest must read/write non-present page tables entries > which caused even worse breakage. > > Understood - I just wanted to make sure that another symptom of the > issue was known in case it came up - some people read the issue > description and were confused as they weren't using any PV guests, only > seeing the specific application crashes under dom0 dom0 is a PV guest so it is affected. David