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=-8.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 35E37C43461 for ; Tue, 8 Sep 2020 07:26:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9C5EE21D20 for ; Tue, 8 Sep 2020 07:26:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9C5EE21D20 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id EBB956B0002; Tue, 8 Sep 2020 03:26:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E6D096B0037; Tue, 8 Sep 2020 03:26:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D82666B0055; Tue, 8 Sep 2020 03:26:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0086.hostedemail.com [216.40.44.86]) by kanga.kvack.org (Postfix) with ESMTP id C38F06B0002 for ; Tue, 8 Sep 2020 03:26:18 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 84AEF1F08 for ; Tue, 8 Sep 2020 07:26:18 +0000 (UTC) X-FDA: 77239060836.18.board60_390cfe6270d2 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin18.hostedemail.com (Postfix) with ESMTP id 54C6E100ED0FE for ; Tue, 8 Sep 2020 07:26:18 +0000 (UTC) X-HE-Tag: board60_390cfe6270d2 X-Filterd-Recvd-Size: 2230 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf37.hostedemail.com (Postfix) with ESMTP for ; Tue, 8 Sep 2020 07:26:17 +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 57E02AD0F; Tue, 8 Sep 2020 07:26:17 +0000 (UTC) Date: Tue, 8 Sep 2020 09:26:13 +0200 From: Oscar Salvador To: HORIGUCHI =?utf-8?B?TkFPWUEo5aCA5Y+j44CA55u05LmfKQ==?= Cc: "yaoaili126@163.com" , "linux-mm@kvack.org" , "YANGFENG1@kingsoft.com" , Aili Yao , "willy@infradead.org" Subject: Re: [PATCH] Fix incorrect compound page flags store Message-ID: <20200908072603.GA11245@linux> References: <20200908034441.16359-1-yaoaili126@163.com> <20200908070210.GA14393@hori.linux.bs1.fc.nec.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200908070210.GA14393@hori.linux.bs1.fc.nec.co.jp> User-Agent: Mutt/1.10.1 (2018-07-13) X-Rspamd-Queue-Id: 54C6E100ED0FE X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 Content-Transfer-Encoding: quoted-printable 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, Sep 08, 2020 at 07:02:12AM +0000, HORIGUCHI NAOYA(=E5=A0=80=E5=8F= =A3 =E7=9B=B4=E4=B9=9F) wrote: > On Mon, Sep 07, 2020 at 08:44:42PM -0700, yaoaili126@163.com wrote: > > From: Aili Yao > >=20 > > PageHuge(p) branch will never be true,but for compound page we need t= o set page_flags to correct value. > >=20 > > Reviewed-by: Matthew Wilcox (Oracle) > > Signed-off-by: Yang Feng < yangfeng1@kingsoft.com> > > Signed-off-by: Aili Yao >=20 > I found that this PageHuge() check is removed and no long exists > in the latest mmotm, so we don't have worry about it. I might be missing something, so bear with me. It is true that the PageHuge check is gone, but we are storing the page's flags in page_flags, even if the page is a tail (e.g: part of a compound = page ). Should not we store heads' flags instead? AFAICS, hpage contains either the head of the compound page, or the page itself in case it is a normal page. --=20 Oscar Salvador SUSE L3