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=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, 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 BF105C433DB for ; Wed, 13 Jan 2021 08:30:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 787AC2333B for ; Wed, 13 Jan 2021 08:30:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726803AbhAMIag (ORCPT ); Wed, 13 Jan 2021 03:30:36 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:41776 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726546AbhAMIaf (ORCPT ); Wed, 13 Jan 2021 03:30:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610526549; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SnkNq7WMI2CVWcX/yAHgyPl0w9p5JWaNoF5mq+QCvB0=; b=JWaw/395giL7SrqN1yqJBJL5Ttl96cL/DO9EcBFuomRltIz+NUNZLUrYVvPwA9luADsCch BebzMpRgWveM+rsNHln5iqX658zkkNRbrlMz7a0uPVwjEkEWDUorTdX9ERwfmLS/yH5cPg 7H4RecTcE9lm6Uz80oMIpXd4/BtfijE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-577-XqfY1E7jNbO_kaHy5Xz8Hg-1; Wed, 13 Jan 2021 03:29:05 -0500 X-MC-Unique: XqfY1E7jNbO_kaHy5Xz8Hg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BAD7A801F98; Wed, 13 Jan 2021 08:29:03 +0000 (UTC) Received: from [10.36.114.135] (ovpn-114-135.ams2.redhat.com [10.36.114.135]) by smtp.corp.redhat.com (Postfix) with ESMTP id C095F7046A; Wed, 13 Jan 2021 08:29:01 +0000 (UTC) Subject: Re: [PATCH v3 2/6] mm: Teach pfn_to_online_page() to consider subsection validity To: Dan Williams , linux-mm@kvack.org Cc: Qian Cai , Michal Hocko , Oscar Salvador , vishal.l.verma@intel.com, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org References: <161052331545.1805594.2356512831689786960.stgit@dwillia2-desk3.amr.corp.intel.com> <161052332755.1805594.9846390935351758277.stgit@dwillia2-desk3.amr.corp.intel.com> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <230efa36-9192-fe52-b8b6-16b2feafb70b@redhat.com> Date: Wed, 13 Jan 2021 09:29:00 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <161052332755.1805594.9846390935351758277.stgit@dwillia2-desk3.amr.corp.intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 13.01.21 08:35, Dan Williams wrote: > pfn_section_valid() determines pfn validity on subsection granularity > where pfn_valid() may be limited to coarse section granularity. > Explicitly validate subsections after pfn_valid() succeeds. > > Fixes: b13bc35193d9 ("mm/hotplug: invalid PFNs from pfn_to_online_page()") > Cc: Qian Cai > Cc: Michal Hocko > Cc: Oscar Salvador > Reported-by: David Hildenbrand > Signed-off-by: Dan Williams > --- > mm/memory_hotplug.c | 24 ++++++++++++++++++++---- > 1 file changed, 20 insertions(+), 4 deletions(-) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 55a69d4396e7..9f37f8a68da4 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -308,11 +308,27 @@ static int check_hotplug_memory_addressable(unsigned long pfn, > struct page *pfn_to_online_page(unsigned long pfn) > { > unsigned long nr = pfn_to_section_nr(pfn); > + struct mem_section *ms; > + > + if (nr >= NR_MEM_SECTIONS) > + return NULL; > + > + ms = __nr_to_section(nr); > + if (!online_section(ms)) > + return NULL; > + > + /* > + * Save some code text when online_section() + > + * pfn_section_valid() are sufficient. > + */ > + if (IS_ENABLED(CONFIG_HAVE_ARCH_PFN_VALID)) > + if (!pfn_valid(pfn)) > + return NULL; Nit: if (IS_ENABLED(CONFIG_HAVE_ARCH_PFN_VALID) && !pfn_valid(pfn)) Reviewed-by: David Hildenbrand -- Thanks, David / dhildenb