From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-f71.google.com (mail-pl0-f71.google.com [209.85.160.71]) by kanga.kvack.org (Postfix) with ESMTP id 100276B2349 for ; Wed, 22 Aug 2018 04:00:31 -0400 (EDT) Received: by mail-pl0-f71.google.com with SMTP id t4-v6so648351plo.0 for ; Wed, 22 Aug 2018 01:00:31 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id s12-v6si1040220plr.120.2018.08.22.01.00.29 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 22 Aug 2018 01:00:29 -0700 (PDT) Date: Wed, 22 Aug 2018 10:00:25 +0200 From: Michal Hocko Subject: Re: [PATCH v2 0/2] mm: soft-offline: fix race against page allocation Message-ID: <20180822080025.GD29735@dhcp22.suse.cz> References: <1531805552-19547-1-git-send-email-n-horiguchi@ah.jp.nec.com> <20180815154334.f3eecd1029a153421631413a@linux-foundation.org> <20180822013748.GA10343@hori1.linux.bs1.fc.nec.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180822013748.GA10343@hori1.linux.bs1.fc.nec.co.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Naoya Horiguchi Cc: Andrew Morton , "linux-mm@kvack.org" , "xishi.qiuxishi@alibaba-inc.com" , "zy.zhengyi@alibaba-inc.com" , "linux-kernel@vger.kernel.org" , Mike Kravetz On Wed 22-08-18 01:37:48, Naoya Horiguchi wrote: > On Wed, Aug 15, 2018 at 03:43:34PM -0700, Andrew Morton wrote: > > On Tue, 17 Jul 2018 14:32:30 +0900 Naoya Horiguchi wrote: > > > > > I've updated the patchset based on feedbacks: > > > > > > - updated comments (from Andrew), > > > - moved calling set_hwpoison_free_buddy_page() from mm/migrate.c to mm/memory-failure.c, > > > which is necessary to check the return code of set_hwpoison_free_buddy_page(), > > > - lkp bot reported a build error when only 1/2 is applied. > > > > > > > mm/memory-failure.c: In function 'soft_offline_huge_page': > > > > >> mm/memory-failure.c:1610:8: error: implicit declaration of function > > > > 'set_hwpoison_free_buddy_page'; did you mean 'is_free_buddy_page'? > > > > [-Werror=implicit-function-declaration] > > > > if (set_hwpoison_free_buddy_page(page)) > > > > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > is_free_buddy_page > > > > cc1: some warnings being treated as errors > > > > > > set_hwpoison_free_buddy_page() is defined in 2/2, so we can't use it > > > in 1/2. Simply doing s/set_hwpoison_free_buddy_page/!TestSetPageHWPoison/ > > > will fix this. > > > > > > v1: https://lkml.org/lkml/2018/7/12/968 > > > > > > > Quite a bit of discussion on these two, but no actual acks or > > review-by's? > > Really sorry for late response. > Xishi provided feedback on previous version, but no final ack/reviewed-by. > This fix should work on the reported issue, but rewriting soft-offlining > without PageHWPoison flag would be the better fix (no actual patch yet.) If we can go with the later the I would obviously prefer that. I cannot promise to work on the patch though. I can help with reviewing of course. If this is important enough that people are hitting the issue in normal workloads then sure, let's go with the simple fix and continue on top of that. -- Michal Hocko SUSE Labs