From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk1-f199.google.com (mail-qk1-f199.google.com [209.85.222.199]) by kanga.kvack.org (Postfix) with ESMTP id 9D6476B000A for ; Thu, 15 Nov 2018 01:19:40 -0500 (EST) Received: by mail-qk1-f199.google.com with SMTP id y83so42557977qka.7 for ; Wed, 14 Nov 2018 22:19:40 -0800 (PST) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id t63-v6si843457qkc.113.2018.11.14.22.19.39 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 14 Nov 2018 22:19:39 -0800 (PST) Date: Thu, 15 Nov 2018 14:19:23 +0800 From: Dave Young 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> Sender: owner-linux-mm@kvack.org List-ID: 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" 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