From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754738Ab2I0M2N (ORCPT ); Thu, 27 Sep 2012 08:28:13 -0400 Received: from mail-da0-f46.google.com ([209.85.210.46]:40863 "EHLO mail-da0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752458Ab2I0M2M (ORCPT ); Thu, 27 Sep 2012 08:28:12 -0400 Message-ID: <50644639.9000804@gmail.com> Date: Thu, 27 Sep 2012 20:27:37 +0800 From: Ni zhan Chen User-Agent: Mozilla/5.0 (X11; Linux i686; rv:15.0) Gecko/20120827 Thunderbird/15.0 MIME-Version: 1.0 To: wency@cn.fujitsu.com CC: linux-mm@kvack.org, linux-kernel@vger.kernel.org, rientjes@google.com, liuj97@gmail.com, len.brown@intel.com, benh@kernel.crashing.org, paulus@samba.org, minchan.kim@gmail.com, akpm@linux-foundation.org, kosaki.motohiro@jp.fujitsu.com, isimatu.yasuaki@jp.fujitsu.com Subject: Re: [PATCH 3/4] memory-hotplug: clear hwpoisoned flag when onlining pages References: <1348724705-23779-1-git-send-email-wency@cn.fujitsu.com> <1348724705-23779-4-git-send-email-wency@cn.fujitsu.com> In-Reply-To: <1348724705-23779-4-git-send-email-wency@cn.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/27/2012 01:45 PM, wency@cn.fujitsu.com wrote: > From: Wen Congyang > > hwpoisoned may set when we offline a page by the sysfs interface > /sys/devices/system/memory/soft_offline_page or > /sys/devices/system/memory/hard_offline_page. If we don't clear > this flag when onlining pages, this page can't be freed, and will > not in free list. So we can't offline these pages again. So we > should clear this flag when onlining pages. page hwpoisoned maybe cause by a multi-bit ECC memory or cache failure, so this page should not be used, why you online and free it again? can any users use it? > > CC: David Rientjes > CC: Jiang Liu > CC: Len Brown > CC: Benjamin Herrenschmidt > CC: Paul Mackerras > Cc: Minchan Kim > CC: Andrew Morton > CC: KOSAKI Motohiro > CC: Yasuaki Ishimatsu > Signed-off-by: Wen Congyang > --- > mm/memory_hotplug.c | 8 ++++++++ > 1 files changed, 8 insertions(+), 0 deletions(-) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 6a5b90d..9a5b10f 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -431,6 +431,14 @@ EXPORT_SYMBOL_GPL(__online_page_increment_counters); > > void __online_page_free(struct page *page) > { > +#ifdef CONFIG_MEMORY_FAILURE > + /* The page may be marked HWPoisoned by soft/hard offline page */ > + if (PageHWPoison(page)) { > + atomic_long_sub(1, &mce_bad_pages); > + ClearPageHWPoison(page); > + } > +#endif > + > ClearPageReserved(page); > init_page_count(page); > __free_page(page);