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=-8.5 required=3.0 tests=INCLUDES_PATCH, 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 5730DC47404 for ; Wed, 9 Oct 2019 14:43:26 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2C739206B6 for ; Wed, 9 Oct 2019 14:43:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C739206B6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C01E88E0005; Wed, 9 Oct 2019 10:43:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BB1AE8E0003; Wed, 9 Oct 2019 10:43:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AC73D8E0005; Wed, 9 Oct 2019 10:43:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0253.hostedemail.com [216.40.44.253]) by kanga.kvack.org (Postfix) with ESMTP id 8ED428E0003 for ; Wed, 9 Oct 2019 10:43:25 -0400 (EDT) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 2FB8F181AC9AE for ; Wed, 9 Oct 2019 14:43:25 +0000 (UTC) X-FDA: 76024514370.15.ray12_1dcee46ef4637 X-HE-Tag: ray12_1dcee46ef4637 X-Filterd-Recvd-Size: 2370 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf01.hostedemail.com (Postfix) with ESMTP for ; Wed, 9 Oct 2019 14:43:24 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id A297DAD12; Wed, 9 Oct 2019 14:43:23 +0000 (UTC) Date: Wed, 9 Oct 2019 16:43:23 +0200 From: Michal Hocko To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Naoya Horiguchi , Andrew Morton Subject: Re: [PATCH v2 2/2] mm/memory-failure.c: Don't access uninitialized memmaps in memory_failure() Message-ID: <20191009144323.GH6681@dhcp22.suse.cz> References: <20191009142435.3975-1-david@redhat.com> <20191009142435.3975-3-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191009142435.3975-3-david@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) 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 Wed 09-10-19 16:24:35, David Hildenbrand wrote: > We should check for pfn_to_online_page() to not access uninitialized > memmaps. Reshuffle the code so we don't have to duplicate the error > message. > > Cc: Naoya Horiguchi > Cc: Andrew Morton > Cc: Michal Hocko > Signed-off-by: David Hildenbrand > --- > mm/memory-failure.c | 14 ++++++++------ > 1 file changed, 8 insertions(+), 6 deletions(-) > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 7ef849da8278..e866e6e5660b 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1253,17 +1253,19 @@ int memory_failure(unsigned long pfn, int flags) > if (!sysctl_memory_failure_recovery) > panic("Memory failure on page %lx", pfn); > > - if (!pfn_valid(pfn)) { > + p = pfn_to_online_page(pfn); > + if (!p) { > + if (pfn_valid(pfn)) { > + pgmap = get_dev_pagemap(pfn, NULL); > + if (pgmap) > + return memory_failure_dev_pagemap(pfn, flags, > + pgmap); > + } > pr_err("Memory failure: %#lx: memory outside kernel control\n", > pfn); > return -ENXIO; Don't we need that earlier at hwpoison_inject level? -- Michal Hocko SUSE Labs