From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753804Ab3KKNEB (ORCPT ); Mon, 11 Nov 2013 08:04:01 -0500 Received: from smtp.citrix.com ([66.165.176.89]:36985 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753150Ab3KKNDx (ORCPT ); Mon, 11 Nov 2013 08:03:53 -0500 X-IronPort-AV: E=Sophos;i="4.93,677,1378857600"; d="scan'208";a="73121585" Message-ID: <1384175027.19117.15.camel@kazak.uk.xensource.com> Subject: Re: [PATCH] xen/arm: pfn_to_mfn and mfn_to_pfn return the argument if nothing is in the p2m From: Ian Campbell To: Stefano Stabellini CC: , , Date: Mon, 11 Nov 2013 13:03:47 +0000 In-Reply-To: <1384174231-27176-1-git-send-email-stefano.stabellini@eu.citrix.com> References: <1384174231-27176-1-git-send-email-stefano.stabellini@eu.citrix.com> Organization: Citrix Systems, Inc. Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4-3 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.30.203.1] X-DLP: MIA1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2013-11-11 at 12:50 +0000, Stefano Stabellini wrote: > Some common Xen drivers, like balloon.c, call pfn_to_mfn and mfn_to_pfn > even for autotranslate guests, expecting the argument back. > The following commit broke these drivers by changing the behavior of > pfn_to_mfn and mfn_to_pfn: > > commit 4a19138c6505e224d9f4cc2fe9ada9188d7100ea > Author: Stefano Stabellini > Date: Thu Oct 17 16:22:27 2013 +0000 > > arm/xen,arm64/xen: introduce p2m > > They now return INVALID_P2M_ENTRY if Linux doesn't actually know what is > the mfn backing a pfn or what is the pfn corresponding to an mfn. > Fix the regression by switching to the old behavior. > > Signed-off-by: Stefano Stabellini Acked-by: Ian Campbell I tripped over this on Friday and my local hack was identical, hence also: Tested-by: Ian Campbell Ian.