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=-7.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B94B3C48BC2 for ; Mon, 28 Jun 2021 01:12:31 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 54D8F61A0F for ; Mon, 28 Jun 2021 01:12:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 54D8F61A0F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 56BBD8D000A; Sun, 27 Jun 2021 21:12:29 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 51CA86B009F; Sun, 27 Jun 2021 21:12:29 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3BCDF8D000A; Sun, 27 Jun 2021 21:12:29 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0134.hostedemail.com [216.40.44.134]) by kanga.kvack.org (Postfix) with ESMTP id 098066B009E for ; Sun, 27 Jun 2021 21:12:28 -0400 (EDT) Received: from smtpin38.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id EE2238249980 for ; Mon, 28 Jun 2021 01:12:28 +0000 (UTC) X-FDA: 78301357176.38.91D0E21 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf27.hostedemail.com (Postfix) with ESMTP id 83F8A8019365 for ; Mon, 28 Jun 2021 01:12:28 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 3DC08619C5; Mon, 28 Jun 2021 01:12:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1624842747; bh=jHVvl6fcFfg+IVQ3lBpd7cBJiC21/SiQ2M2n/J/aDeQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=aus9ryL+DgdKH4ZNAJ5wqeFEe6w9+xkQn3TmuhatvYPqjRvTfTCqQsNQm3nJrmYD/ X3DX2v1FqasZlVOaBS1sW/lXxvheF8cEwJVuOjRQZm7cTjQNhBT3i/tCFbtBeIq3yj bupVyrvJDARUQXHC8Ly6sHJgcxIsv6qUTNCdNM7w= Date: Sun, 27 Jun 2021 18:12:26 -0700 From: Andrew Morton To: Christophe Leroy Cc: Steven Price , linux-mm@kvack.org, Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , dja@axtens.net, "Oliver O'Halloran" , linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3] mm: pagewalk: Fix walk for hugepage tables Message-Id: <20210627181226.983d899cc30c02420e1a6af5@linux-foundation.org> In-Reply-To: <38d04410700c8d02f28ba37e020b62c55d6f3d2c.1624597695.git.christophe.leroy@csgroup.eu> References: <38d04410700c8d02f28ba37e020b62c55d6f3d2c.1624597695.git.christophe.leroy@csgroup.eu> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=aus9ryL+; spf=pass (imf27.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Stat-Signature: x8z4kjkh3azgfosktn76nyue37wjy9uc X-Rspamd-Queue-Id: 83F8A8019365 X-Rspamd-Server: rspam06 X-HE-Tag: 1624842748-218026 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 Fri, 25 Jun 2021 05:10:12 +0000 (UTC) Christophe Leroy wrote: > Pagewalk ignores hugepd entries and walk down the tables > as if it was traditionnal entries, leading to crazy result. > > Add walk_hugepd_range() and use it to walk hugepage tables. More details, please? I assume "crazy result" is userspace visible? For how long has this bug existed? Is a -stable backport needed? Has a Fixes: commit been identified? etcetera!