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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 2BC21C433E0 for ; Wed, 8 Jul 2020 09:27:02 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id CF56B2065C for ; Wed, 8 Jul 2020 09:27:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CF56B2065C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 3CE318D0035; Wed, 8 Jul 2020 05:27:01 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 357F18D000D; Wed, 8 Jul 2020 05:27:01 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 247238D0035; Wed, 8 Jul 2020 05:27:01 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0187.hostedemail.com [216.40.44.187]) by kanga.kvack.org (Postfix) with ESMTP id 0A3DF8D000D for ; Wed, 8 Jul 2020 05:27:01 -0400 (EDT) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id C019F180AD807 for ; Wed, 8 Jul 2020 09:27:00 +0000 (UTC) X-FDA: 77014379400.05.door17_231074026ebc Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin05.hostedemail.com (Postfix) with ESMTP id 9CE7818023455 for ; Wed, 8 Jul 2020 09:27:00 +0000 (UTC) X-HE-Tag: door17_231074026ebc X-Filterd-Recvd-Size: 3179 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf35.hostedemail.com (Postfix) with ESMTP for ; Wed, 8 Jul 2020 09:27:00 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id E831EAD4D; Wed, 8 Jul 2020 09:26:58 +0000 (UTC) Subject: Re: [PATCH v4 04/11] mm/hugetlb: make hugetlb migration callback CMA aware To: Michal Hocko , Joonsoo Kim Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@lge.com, Christoph Hellwig , Roman Gushchin , Mike Kravetz , Naoya Horiguchi , "Aneesh Kumar K.V" References: <1594107889-32228-1-git-send-email-iamjoonsoo.kim@lge.com> <1594107889-32228-5-git-send-email-iamjoonsoo.kim@lge.com> <20200708071602.GB16543@js1304-desktop> <20200708074103.GD7271@dhcp22.suse.cz> From: Vlastimil Babka Message-ID: <8549326e-7485-dd6d-1fa1-a899228b9b2f@suse.cz> Date: Wed, 8 Jul 2020 11:26:54 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <20200708074103.GD7271@dhcp22.suse.cz> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 9CE7818023455 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 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 7/8/20 9:41 AM, Michal Hocko wrote: > On Wed 08-07-20 16:16:02, Joonsoo Kim wrote: >> On Tue, Jul 07, 2020 at 01:22:31PM +0200, Vlastimil Babka wrote: >> >> Simply, I call memalloc_nocma_{save,restore} in new_non_cma_page(). It >> would not cause any problem. > > I believe a proper fix is the following. The scope is really defined for > FOLL_LONGTERM pins and pushing it inside check_and_migrate_cma_pages > will solve the problem as well but it imho makes more sense to do it in > the caller the same way we do for any others. > > Fixes: 9a4e9f3b2d73 ("mm: update get_user_pages_longterm to migrate pages allocated from CMA region") Agreed. > > I am not sure this is worth backporting to stable yet. CC Aneesh. Context: since check_and_migrate_cma_pages() calls __get_user_pages_locked(), it should also be called under memalloc_nocma_save(). > diff --git a/mm/gup.c b/mm/gup.c > index de9e36262ccb..75980dd5a2fc 100644 > --- a/mm/gup.c > +++ b/mm/gup.c > @@ -1794,7 +1794,6 @@ static long __gup_longterm_locked(struct task_struct *tsk, > vmas_tmp, NULL, gup_flags); > > if (gup_flags & FOLL_LONGTERM) { > - memalloc_nocma_restore(flags); > if (rc < 0) > goto out; > > @@ -1802,11 +1801,13 @@ static long __gup_longterm_locked(struct task_struct *tsk, > for (i = 0; i < rc; i++) > put_page(pages[i]); > rc = -EOPNOTSUPP; > + memalloc_nocma_restore(flags); > goto out; > } > > rc = check_and_migrate_cma_pages(tsk, mm, start, rc, pages, > vmas_tmp, gup_flags); > + memalloc_nocma_restore(flags); > } > > out: >