From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8CB9AC43441 for ; Tue, 13 Nov 2018 08:02:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4D0E122507 for ; Tue, 13 Nov 2018 08:02:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4D0E122507 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731167AbeKMR7d (ORCPT ); Tue, 13 Nov 2018 12:59:33 -0500 Received: from mx2.suse.de ([195.135.220.15]:34354 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730421AbeKMR7d (ORCPT ); Tue, 13 Nov 2018 12:59:33 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id D1ED1B160; Tue, 13 Nov 2018 08:02:35 +0000 (UTC) Date: Tue, 13 Nov 2018 09:02:34 +0100 From: Michal Hocko To: Andrew Morton Cc: linux-mm@kvack.org, Oscar Salvador , Baoquan He , LKML Subject: Re: [RFC PATCH 4/5] mm, memory_hotplug: print reason for the offlining failure Message-ID: <20181113080234.GI15120@dhcp22.suse.cz> References: <20181107101830.17405-1-mhocko@kernel.org> <20181107101830.17405-5-mhocko@kernel.org> <20181107140413.2c0061e440123be76bf419bf@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181107140413.2c0061e440123be76bf419bf@linux-foundation.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 07-11-18 14:04:13, Andrew Morton wrote: > On Wed, 7 Nov 2018 11:18:29 +0100 Michal Hocko wrote: > > > From: Michal Hocko > > > > The memory offlining failure reporting is inconsistent and insufficient. > > Some error paths simply do not report the failure to the log at all. > > When we do report there are no details about the reason of the failure > > and there are several of them which makes memory offlining failures > > hard to debug. > > > > Make sure that the > > memory offlining [mem %#010llx-%#010llx] failed > > message is printed for all failures and also provide a short textual > > reason for the failure e.g. > > > > [ 1984.506184] rac1 kernel: memory offlining [mem 0x82600000000-0x8267fffffff] failed due to signal backoff > > > > this tells us that the offlining has failed because of a signal pending > > aka user intervention. > > > > ... > > Some of these messages will come out looking a bit odd. > > > @@ -1573,7 +1576,8 @@ static int __ref __offline_pages(unsigned long start_pfn, > > MIGRATE_MOVABLE, true); > > if (ret) { > > mem_hotplug_done(); > > - return ret; > > + reason = "failed to isolate range"; > > "memory offlining [mem ...] failed due to failed to isolate range" > > > + goto failed_removal > > } > > > > arg.start_pfn = start_pfn; > > @@ -1582,15 +1586,19 @@ static int __ref __offline_pages(unsigned long start_pfn, > > > > ret = memory_notify(MEM_GOING_OFFLINE, &arg); > > ret = notifier_to_errno(ret); > > - if (ret) > > - goto failed_removal; > > + if (ret) { > > + reason = "notifiers failure"; > > "memory offlining [mem ...] failed due to notifiers failure" > > > @@ -1607,8 +1615,10 @@ static int __ref __offline_pages(unsigned long start_pfn, > > * actually in order to make hugetlbfs's object counting consistent. > > */ > > ret = dissolve_free_huge_pages(start_pfn, end_pfn); > > - if (ret) > > - goto failed_removal; > > + if (ret) { > > + reason = "fails to disolve hugetlb pages"; > > "memory offlining [mem ...] failed due to fails to disolve hugetlb pages" > > > Fix: > > --- a/mm/memory_hotplug.c~mm-memory_hotplug-print-reason-for-the-offlining-failure-fix > +++ a/mm/memory_hotplug.c > @@ -1576,7 +1576,7 @@ static int __ref __offline_pages(unsigne > MIGRATE_MOVABLE, true); > if (ret) { > mem_hotplug_done(); > - reason = "failed to isolate range"; > + reason = "failure to isolate range"; > goto failed_removal > } 0day has noticed the missing ; here. Andrew, could you pick up the follow up fix please? commit 614212af5c20126aea1edaceb78aa586e19802cf Author: Michal Hocko Date: Tue Nov 13 09:01:50 2018 +0100 fold me "mm, memory_hotplug: print reason for the offlining failure" diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index f5f1b2a27cb3..c82193db4be6 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1581,7 +1581,7 @@ static int __ref __offline_pages(unsigned long start_pfn, if (ret) { mem_hotplug_done(); reason = "failure to isolate range"; - goto failed_removal + goto failed_removal; } arg.start_pfn = start_pfn; -- Michal Hocko SUSE Labs