Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754455AbaDGPco (ORCPT ); Mon, 7 Apr 2014 11:32:44 -0400 Received: from smtp.citrix.com ([66.165.176.89]:17698 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750965AbaDGPcn (ORCPT ); Mon, 7 Apr 2014 11:32:43 -0400 X-IronPort-AV: E=Sophos;i="4.97,810,1389744000"; d="scan'208";a="118724411" Message-ID: <5342C517.2020305@citrix.com> Date: Mon, 7 Apr 2014 16:32:39 +0100 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: Mel Gorman CC: Linus Torvalds , Cyrill Gorcunov , Peter Anvin , Ingo Molnar , Steven Noonan , Rik van Riel , Andrew Morton , Peter Zijlstra , Andrea Arcangeli , Linux-MM , Linux-X86 , LKML Subject: Re: [PATCH 2/3] x86: Define _PAGE_NUMA with unused physical address bits PMD and PTE levels References: <1396883443-11696-1-git-send-email-mgorman@suse.de> <1396883443-11696-3-git-send-email-mgorman@suse.de> In-Reply-To: <1396883443-11696-3-git-send-email-mgorman@suse.de> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.2.76] X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/04/14 16:10, Mel Gorman wrote: > _PAGE_NUMA is currently an alias of _PROT_PROTNONE to trap NUMA hinting > faults. As the bit is shared care is taken that _PAGE_NUMA is only used in > places where _PAGE_PROTNONE could not reach but this still causes problems > on Xen and conceptually difficult. The problem with Xen guests occurred because mprotect() /was/ confusing PROTNONE mappings with _PAGE_NUMA and clearing the non-existant NUMA hints. 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/