From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx156.postini.com [74.125.245.156]) by kanga.kvack.org (Postfix) with SMTP id 775A16B006E for ; Thu, 15 Nov 2012 16:27:08 -0500 (EST) Received: by mail-pb0-f41.google.com with SMTP id xa7so1584639pbc.14 for ; Thu, 15 Nov 2012 13:27:07 -0800 (PST) Date: Thu, 15 Nov 2012 13:27:05 -0800 (PST) From: David Rientjes Subject: Re: [PATCH] mm: fix a regression with HIGHMEM introduced by changeset 7f1290f2f2a4d In-Reply-To: <20121115112454.e582a033.akpm@linux-foundation.org> Message-ID: References: <1352165517-9732-1-git-send-email-jiang.liu@huawei.com> <20121106124315.79deb2bc.akpm@linux-foundation.org> <50A3B013.4030207@gmail.com> <20121115112454.e582a033.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Jiang Liu , Jiang Liu , Maciej Rutecki , Jianguo Wu , Chris Clayton , "Rafael J. Wysocki" , Mel Gorman , Minchan Kim , KAMEZAWA Hiroyuki , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Daniel Vetter On Thu, 15 Nov 2012, Andrew Morton wrote: > From: Andrew Morton > Subject: revert "mm: fix-up zone present pages" > > Revert > > commit 7f1290f2f2a4d2c3f1b7ce8e87256e052ca23125 > Author: Jianguo Wu > AuthorDate: Mon Oct 8 16:33:06 2012 -0700 > Commit: Linus Torvalds > CommitDate: Tue Oct 9 16:22:54 2012 +0900 > > mm: fix-up zone present pages > > > That patch tried to fix a issue when calculating zone->present_pages, but > it caused a regression on 32bit systems with HIGHMEM. With that > changeset, reset_zone_present_pages() resets all zone->present_pages to > zero, and fixup_zone_present_pages() is called to recalculate > zone->present_pages when the boot allocator frees core memory pages into > buddy allocator. Because highmem pages are not freed by bootmem > allocator, all highmem zones' present_pages becomes zero. > > Various options for improving the situation are being discussed but for > now, let's return to the 3.6 code. > > Cc: Jianguo Wu > Cc: Jiang Liu > Cc: Petr Tesarik > Cc: "Luck, Tony" > Cc: Mel Gorman > Cc: Yinghai Lu > Cc: Minchan Kim > Cc: Johannes Weiner > Cc: David Rientjes > Signed-off-by: Andrew Morton Acked-by: David Rientjes -- 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