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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 3C606C433E0 for ; Tue, 5 Jan 2021 14:25:00 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B431D2065C for ; Tue, 5 Jan 2021 14:24:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B431D2065C Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 153A58D007F; Tue, 5 Jan 2021 09:24:59 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 102E48D006E; Tue, 5 Jan 2021 09:24:59 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 019B08D007F; Tue, 5 Jan 2021 09:24:58 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0049.hostedemail.com [216.40.44.49]) by kanga.kvack.org (Postfix) with ESMTP id DE4F08D006E for ; Tue, 5 Jan 2021 09:24:58 -0500 (EST) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id A8B01181AEF0B for ; Tue, 5 Jan 2021 14:24:58 +0000 (UTC) X-FDA: 77671943076.18.nail91_1706d68274d9 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin18.hostedemail.com (Postfix) with ESMTP id 7D3AE100ED0F8 for ; Tue, 5 Jan 2021 14:24:58 +0000 (UTC) X-HE-Tag: nail91_1706d68274d9 X-Filterd-Recvd-Size: 3032 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf39.hostedemail.com (Postfix) with ESMTP for ; Tue, 5 Jan 2021 14:24:57 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1609856696; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=oD8OhFiTFS91oSo/GxxMnZWrLGad6kBBv+IR7HZxg1Q=; b=JP/nz1QiqHC4h0BO/jt/cnqiI07Z9EoE3GIgDqexKBUfc0T0Q57GZTpMpMn6nJ4KkV9Tkn u+m9AIyTm8UNWZPxMO5ku3GMG5DprV0zr/mon1H3dTKJkoaLscfW+W9i+Fi9lhZXFBxS9G VLXhzInzyruCVVvuW3P9Ve2PwytpzY8= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 9238FACC6; Tue, 5 Jan 2021 14:24:56 +0000 (UTC) Date: Tue, 5 Jan 2021 15:24:54 +0100 From: Michal Hocko To: Jan Stancek Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, ziy@nvidia.com, shy828301@gmail.com, jack@suse.cz, willy@infradead.org, mgorman@suse.de, songliubraving@fb.com, akpm@linux-foundation.org Subject: Re: [PATCH] mm: migrate: initialize err in do_migrate_pages Message-ID: <20210105142454.GH13207@dhcp22.suse.cz> References: <456a021c7ef3636d7668cec9dcb4a446a4244812.1609855564.git.jstancek@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <456a021c7ef3636d7668cec9dcb4a446a4244812.1609855564.git.jstancek@redhat.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue 05-01-21 15:14:20, Jan Stancek wrote: > After commit 236c32eb1096 ("mm: migrate: clean up migrate_prep{_local}")', > do_migrate_pages can return uninitialized variable 'err' (which is > propagated to user-space as error) when 'from' and 'to' nodesets > are identical. This can be reproduced with LTP migrate_pages01, > which calls migrate_pages() with same set for both old/new_nodes. > > Add 'err' initialization back. > > Fixes: 236c32eb1096 ("mm: migrate: clean up migrate_prep{_local}") > Cc: Zi Yan > Cc: Yang Shi > Cc: Jan Kara > Cc: Matthew Wilcox > Cc: Mel Gorman > Cc: Michal Hocko > Cc: Song Liu > Cc: Andrew Morton > Signed-off-by: Jan Stancek Acked-by: Michal Hocko Thanks! > --- > mm/mempolicy.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index 8cf96bd21341..2c3a86502053 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -1111,7 +1111,7 @@ int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from, > const nodemask_t *to, int flags) > { > int busy = 0; > - int err; > + int err = 0; > nodemask_t tmp; > > migrate_prep(); > -- > 2.18.1 > -- Michal Hocko SUSE Labs