From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52773) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d3jlL-0005Mw-8Z for qemu-devel@nongnu.org; Thu, 27 Apr 2017 09:47:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d3jlH-0004H8-8q for qemu-devel@nongnu.org; Thu, 27 Apr 2017 09:47:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40958) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d3jlH-0004Fr-2j for qemu-devel@nongnu.org; Thu, 27 Apr 2017 09:47:11 -0400 Date: Thu, 27 Apr 2017 15:47:07 +0200 From: Andrea Arcangeli Message-ID: <20170427134707.GG3508@redhat.com> References: <20170426183721.7482-1-dgilbert@redhat.com> <20170426183721.7482-2-dgilbert@redhat.com> <8a107a40-073c-8181-75aa-e5700f2900a7@de.ibm.com> <20170426190442.GG2394@work-vm> <20170426193743.GF3508@redhat.com> <20170427032037.GE26792@pxdev.xzpeter.org> <750be300-6f14-cbef-4b38-f28751e28032@de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <750be300-6f14-cbef-4b38-f28751e28032@de.ibm.com> Subject: Re: [Qemu-devel] [PATCH 1/2] Postcopy: Force allocation of all-zero precopy pages List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Christian Borntraeger Cc: Peter Xu , "Dr. David Alan Gilbert" , qemu-devel@nongnu.org, quintela@redhat.com, lvivier@redhat.com On Thu, Apr 27, 2017 at 08:44:03AM +0200, Christian Borntraeger wrote: > I have started instrumenting the kernel. I can see a set_pte_at for this address > and I see an (to be understood) invalidation shortly after that which explains > why I get a fault. Sounds great that you can see an invalidation shortly after, that is the real source of the problem. Can you get a stack trace of such invalidation? Thanks! Andrea