From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753144Ab2GIKuo (ORCPT ); Mon, 9 Jul 2012 06:50:44 -0400 Received: from gir.skynet.ie ([193.1.99.77]:42494 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752886Ab2GIKun (ORCPT ); Mon, 9 Jul 2012 06:50:43 -0400 Date: Mon, 9 Jul 2012 11:50:40 +0100 From: Mel Gorman To: Wanpeng Li Cc: linux-mm@kvack.org, Michal Hocko , KAMEZAWA Hiroyuki , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/hugetlb: split out is_hugetlb_entry_migration_or_hwpoison Message-ID: <20120709105040.GT13141@csn.ul.ie> References: <1341828761-11195-1-git-send-email-liwp.linux@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <1341828761-11195-1-git-send-email-liwp.linux@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 09, 2012 at 06:12:41PM +0800, Wanpeng Li wrote: > From: Wanpeng Li > > Code was duplicated in two functions, clean it up. > > Signed-off-by: Wanpeng Li is_hugetlb_entry_migration() now returns true for hwpoisoned pages. In this block if (unlikely(is_hugetlb_entry_migration(entry))) { migration_entry_wait(mm, (pmd_t *)ptep, address); return 0; we now will call migration_entry_wait and return 0 to the fault handler instead of VM_FAULT_HWPOISON_LARGE | VM_FAULT_SET_HINDEX(h - hstates). By co-incidence this might work because migration of hugetlb happens for poisoned pages but it would be just a co-incidence. Some other change in the future such as better support for memory hotplug of regions backed by hugetlbfs may break it again. Superficially, this patch looks broken and the changelog contains no motivation as to why this patch should be merged such as being a pre-requisite for another fix or feature. It just looks like churn for the sake of churn. It might be just me but it feels like I'm seeing a lot more of this style of patch recently on linux-mm and review bandwidth is not infinite :( Nak. -- Mel Gorman SUSE Labs