From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave McCracken Subject: Re: pvops-dom0 console freezes after latest ballooning patch (+possible fix) Date: Wed, 9 Dec 2009 14:20:22 -0600 Message-ID: <200912091420.22303.dcm@mccr.org> References: <846954254.901022.1260386535441.JavaMail.tomcat55@mrmseu0.kundenserver.de> <4B1FFFCA.9060701@goop.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4B1FFFCA.9060701@goop.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jeremy Fitzhardinge , Ronny.Hegewald@online.de Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Wednesday 09 December 2009, Jeremy Fitzhardinge wrote: > On 12/09/09 11:22, Ronny.Hegewald@online.de wrote: > > Setup: xen 3.4.1, 32-bit linux dom0 2.6.31.6 from pvops-git tree from > > 2009-12-03 > > > > > > Since the latest ballooning patch "Add hugepage support to balloon > > driver > > >8d5e9b893324435e0e77b67fe8d2f0523dbe>" i experience dom0 console freezes. > > Additional to that there is a stacktrace about a kernel-bug in > > drivers/xen/balloon.c in line 346, invalide opcode 0000 (i can send the > > full stacktrace if someone is interested). > > Yes, please. Presumably its from the BUG_ON testing the hypercall > return status? > > > The cause for that seems to be that in the > > decrease_reservation-funtion the PageHighMem - check is not executed > > on the assocciated page for the current pfn. Its always the last page > > that got allocated in the for-loop before, when all the pages are > > allocated. > > > > With the attached patch that crashes dont occur anymore. But im not a > > kernel-developer so im not sure that this is the correct fix. > > It looks reasonable to me. Dave? > > J Yes, absolutely. It's the correct fix. Good catch. Dave McCracken Oracle Corp.