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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 39A7EC43460 for ; Wed, 14 Apr 2021 10:50:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1688F6128E for ; Wed, 14 Apr 2021 10:50:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234080AbhDNKuU (ORCPT ); Wed, 14 Apr 2021 06:50:20 -0400 Received: from mx2.suse.de ([195.135.220.15]:59058 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233897AbhDNKuS (ORCPT ); Wed, 14 Apr 2021 06:50:18 -0400 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 24B63AE56; Wed, 14 Apr 2021 10:49:56 +0000 (UTC) Date: Wed, 14 Apr 2021 12:49:53 +0200 From: Oscar Salvador To: Michal Hocko Cc: Mike Kravetz , Andrew Morton , Vlastimil Babka , David Hildenbrand , Muchun Song , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v7 3/7] mm,hugetlb: Clear HPageFreed outside of the lock Message-ID: <20210414104953.GF20886@linux> References: <20210413104747.12177-1-osalvador@suse.de> <20210413104747.12177-4-osalvador@suse.de> <20210414074132.GB20401@linux> <20210414100147.GD20886@linux> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 14, 2021 at 12:32:58PM +0200, Michal Hocko wrote: > Well, to be precise it does the very same thing with memamp struct pages > but that is before the initialization code you have pointed out above. > In this context it just poisons the allocated content which is the GB > page storage. Right. > > I checked, and when we get there in __alloc_bootmem_huge_page, page->private is > > still zeroed, so I guess it should be safe to assume that we do not really need > > to clear the flag in __prep_new_huge_page() routine? > > It would be quite nasty if the struct pages content would be undefined. > Maybe that is possible but then I would rather stick the initialization > into __alloc_bootmem_huge_page. Yes, but I do not think that is really possible unless I missed something. Let us see what Mike thinks of it, if there are no objections, we can get rid of the clearing flag right there. -- Oscar Salvador SUSE L3