From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH v7 2/4] xen/arm: grant: Add another entry to map MFN 1:1 in dom0 p2m Date: Tue, 20 May 2014 12:53:34 +0100 Message-ID: <537B423E.6060708@linaro.org> References: <1400163385-19863-1-git-send-email-julien.grall@linaro.org> <1400163385-19863-3-git-send-email-julien.grall@linaro.org> <5377A674.8090806@linaro.org> <1400492734.32311.33.camel@kazak.uk.xensource.com> <537A131C.7090701@linaro.org> <537B04A9.4050101@citrix.com> <1400575900.25175.4.camel@kazak.uk.xensource.com> <537B3A4B.7030305@linaro.org> <1400585155.6946.2.camel@kazak.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta4.messagelabs.com ([85.158.143.247]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1Wmibx-0004c9-QV for xen-devel@lists.xenproject.org; Tue, 20 May 2014 11:53:38 +0000 Received: by mail-ee0-f54.google.com with SMTP id b57so457638eek.41 for ; Tue, 20 May 2014 04:53:36 -0700 (PDT) In-Reply-To: <1400585155.6946.2.camel@kazak.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: xen-devel@lists.xenproject.org, tim@xen.org, stefano.stabellini@citrix.com, =?UTF-8?B?Um9nZXIgUGF1IE1vbm7DqQ==?= List-Id: xen-devel@lists.xenproject.org On 05/20/2014 12:25 PM, Ian Campbell wrote: > On Tue, 2014-05-20 at 12:19 +0100, Julien Grall wrote: >> FreeBSD is asking to write this buffer to the disk but from what I see >> it mostly contains garbage (full of 0xc2). >> >> I can't find where this comes and wondering if you have any thoughts. > > 0xc2 is the value which Xen uses to scrub pages when debug=y (see > xen/common/page_alloc.c:scrub_one_page). I though about it, but I find strange that the guest is trying to write non-modified page to the disk. I will try to debug a bit more on it. -- Julien Grall