From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yk0-f181.google.com (mail-yk0-f181.google.com [209.85.160.181]) by kanga.kvack.org (Postfix) with ESMTP id 5FBAD6B0031 for ; Mon, 7 Apr 2014 11:32:43 -0400 (EDT) Received: by mail-yk0-f181.google.com with SMTP id 131so5677058ykp.12 for ; Mon, 07 Apr 2014 08:32:43 -0700 (PDT) Received: from SMTP.CITRIX.COM (smtp.citrix.com. [66.165.176.89]) by mx.google.com with ESMTPS id a63si19606354yhk.189.2014.04.07.08.32.42 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 07 Apr 2014 08:32:42 -0700 (PDT) Message-ID: <5342C517.2020305@citrix.com> Date: Mon, 7 Apr 2014 16:32:39 +0100 From: David Vrabel MIME-Version: 1.0 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 Sender: owner-linux-mm@kvack.org List-ID: 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 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org