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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 B880EC43441 for ; Thu, 15 Nov 2018 06:19:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 828C82086B for ; Thu, 15 Nov 2018 06:19:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 828C82086B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728647AbeKOQ0I (ORCPT ); Thu, 15 Nov 2018 11:26:08 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58420 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726574AbeKOQ0H (ORCPT ); Thu, 15 Nov 2018 11:26:07 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8433C58E31; Thu, 15 Nov 2018 06:19:38 +0000 (UTC) Received: from dhcp-128-65.nay.redhat.com (ovpn-12-146.pek2.redhat.com [10.72.12.146]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4D5D15D759; Thu, 15 Nov 2018 06:19:26 +0000 (UTC) Date: Thu, 15 Nov 2018 14:19:23 +0800 From: Dave Young To: David Hildenbrand Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, devel@linuxdriverproject.org, linux-fsdevel@vger.kernel.org, linux-pm@vger.kernel.org, xen-devel@lists.xenproject.org, Andrew Morton , "Kirill A. Shutemov" , Baoquan He , Omar Sandoval , Arnd Bergmann , Matthew Wilcox , Michal Hocko , Lianbo Jiang , Borislav Petkov , "Michael S. Tsirkin" Subject: Re: [PATCH RFC 3/6] kexec: export PG_offline to VMCOREINFO Message-ID: <20181115061923.GA3971@dhcp-128-65.nay.redhat.com> References: <20181114211704.6381-1-david@redhat.com> <20181114211704.6381-4-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181114211704.6381-4-david@redhat.com> User-Agent: Mutt/1.9.5 (2018-04-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Thu, 15 Nov 2018 06:19:38 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi David, On 11/14/18 at 10:17pm, David Hildenbrand wrote: > Let's export PG_offline via PAGE_OFFLINE_MAPCOUNT_VALUE, so > makedumpfile can directly skip pages that are logically offline and the > content therefore stale. It would be good to copy some background info from cover letter to the patch description so that we can get better understanding why this is needed now. BTW, Lianbo is working on a documentation of the vmcoreinfo exported fields. Ccing him so that he is aware of this. Also cc Boris, although I do not want the doc changes blocks this he might have different opinion :) > > Cc: Andrew Morton > Cc: Dave Young > Cc: "Kirill A. Shutemov" > Cc: Baoquan He > Cc: Omar Sandoval > Cc: Arnd Bergmann > Cc: Matthew Wilcox > Cc: Michal Hocko > Cc: "Michael S. Tsirkin" > Signed-off-by: David Hildenbrand > --- > kernel/crash_core.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/kernel/crash_core.c b/kernel/crash_core.c > index 933cb3e45b98..093c9f917ed0 100644 > --- a/kernel/crash_core.c > +++ b/kernel/crash_core.c > @@ -464,6 +464,8 @@ static int __init crash_save_vmcoreinfo_init(void) > VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE); > #ifdef CONFIG_HUGETLB_PAGE > VMCOREINFO_NUMBER(HUGETLB_PAGE_DTOR); > +#define PAGE_OFFLINE_MAPCOUNT_VALUE (~PG_offline) > + VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE); > #endif > > arch_crash_save_vmcoreinfo(); > -- > 2.17.2 > Thanks Dave