From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qa0-f42.google.com (mail-qa0-f42.google.com [209.85.216.42]) by kanga.kvack.org (Postfix) with ESMTP id 0AA946B0160 for ; Wed, 11 Jun 2014 09:58:56 -0400 (EDT) Received: by mail-qa0-f42.google.com with SMTP id dc16so3102415qab.15 for ; Wed, 11 Jun 2014 06:58:55 -0700 (PDT) Received: from qmta10.emeryville.ca.mail.comcast.net (qmta10.emeryville.ca.mail.comcast.net. [2001:558:fe2d:43:76:96:30:17]) by mx.google.com with ESMTP id s49si30544860qgs.97.2014.06.11.06.58.54 for ; Wed, 11 Jun 2014 06:58:55 -0700 (PDT) Date: Wed, 11 Jun 2014 08:58:51 -0500 (CDT) From: Christoph Lameter Subject: Re: [PATCH] x86: numa: drop ZONE_ALIGN In-Reply-To: <20140611092337.35794bc0@redhat.com> Message-ID: References: <20140608181436.17de69ac@redhat.com> <20140609150353.75eff02b@redhat.com> <20140611092337.35794bc0@redhat.com> Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Luiz Capitulino Cc: Yinghai Lu , Tejun Heo , Andrew Morton , Andi Kleen , Rik van Riel , Yasuaki Ishimatsu , Linux MM , Linux Kernel Mailing List , "stable@vger.kernel.org" On Wed, 11 Jun 2014, Luiz Capitulino wrote: > > The zone should not cross the 8M boundary? > > Yes, but the question is: why? zones need to be aligned so that the huge pages order and other page orders allocated from the page allocator are at their "natural alignment". Otherwise huge pages cannot be mapped properly and various I/O devices may encounter issues if they rely on the natural alignment. > My current thinking, after discussing this with David, is to just page > align the memory range. This should fix the hyperv-triggered bug in 2.6.32 > and seems to be the right thing for upstream too. You need to make sure that the page orders can be allocated at their proper boundaries. -- 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