Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756349AbaAISYE (ORCPT ); Thu, 9 Jan 2014 13:24:04 -0500 Received: from smtp02.citrix.com ([66.165.176.63]:56231 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756126AbaAISXz (ORCPT ); Thu, 9 Jan 2014 13:23:55 -0500 X-IronPort-AV: E=Sophos;i="4.95,632,1384300800"; d="scan'208";a="89248592" Message-ID: <52CEE91D.50105@citrix.com> Date: Thu, 9 Jan 2014 18:23:25 +0000 From: David Vrabel User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.16) Gecko/20121215 Iceowl/1.0b1 Icedove/3.0.11 MIME-Version: 1.0 To: Stefano Stabellini CC: Wei Liu , , Ian Campbell , , , Zoltan Kiss , , =?ISO-8859-1?Q?Roger_Pau_Monn=E9?= , Konrad Rzeszutek Wilk Subject: Re: [Xen-devel] [PATCH net-next v3 1/9] xen-netback: Introduce TX grant map definitions References: <1389139818-24458-1-git-send-email-zoltan.kiss@citrix.com> <1389139818-24458-2-git-send-email-zoltan.kiss@citrix.com> <20140109153010.GE12164@zion.uk.xensource.com> <52CEC370.10503@citrix.com> <52CEE084.5000409@citrix.com> In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.2.76] X-DLP: MIA1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/01/14 18:09, Stefano Stabellini wrote: > > I agree, but I think that we have different views on the use case. > To me the m2p_override use case is "everywhere an mfn_to_pfn translation > is required", that unfortunately is potentially everywhere at this time. mfn_to_pfn() cannot be made to work correctly with foreign MFNs. It's a fundamentally unsolvable problem. IMO, the only sensible use of the m2p_override is to cause mfn_to_pfn() to BUG() if a foreign MFN is used. David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/