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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 1B9BFCA9EB9 for ; Tue, 22 Oct 2019 08:08:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DCA3621906 for ; Tue, 22 Oct 2019 08:08:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571731721; bh=+MlWSvS5f8l1gqIcAKPVX8o4bHZEGgrMxsGD7+3vMfI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=KWYPQ8HYlMLGuRJzbsoFPM+Bz8ztJbKfhWMVqycLTkdvxmI2p58D3iUDGS+WQcnSu fBTxw77FhANnKA58KjnPpTG8L4Z/xjiAS+oxasubSRQp+ufsaQZVE4S51/cmnlfwMF 9cJuK8GO94bZFwdvRYg0Xag8L6vs9OFJYbG49rMs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388233AbfJVIIj (ORCPT ); Tue, 22 Oct 2019 04:08:39 -0400 Received: from mx2.suse.de ([195.135.220.15]:56856 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2388047AbfJVIIj (ORCPT ); Tue, 22 Oct 2019 04:08:39 -0400 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 945C8B12D; Tue, 22 Oct 2019 08:08:37 +0000 (UTC) Date: Tue, 22 Oct 2019 10:08:35 +0200 From: Michal Hocko To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Alexander Duyck , Andrew Morton , Anshuman Khandual , Dan Williams , Mel Gorman , Mike Rapoport , Mike Rapoport , Oscar Salvador , Pavel Tatashin , Pavel Tatashin , Pingfan Liu , Qian Cai , Vlastimil Babka , Wei Yang Subject: Re: [PATCH v2 0/2] mm: Memory offlining + page isolation cleanups Message-ID: <20191022080835.GZ9379@dhcp22.suse.cz> References: <20191021172353.3056-1-david@redhat.com> <25d3f071-3268-298b-e0c8-9c307d1015fe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <25d3f071-3268-298b-e0c8-9c307d1015fe@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 22-10-19 08:52:28, David Hildenbrand wrote: > On 21.10.19 19:23, David Hildenbrand wrote: > > Two cleanups that popped up while working on (and discussing) virtio-mem: > > https://lkml.org/lkml/2019/9/19/463 > > > > Tested with DIMMs on x86. > > > > As discussed with michal in v1, I'll soon look into removing the use > > of PG_reserved during memory onlining completely - most probably > > disallowing to offline memory blocks with holes, cleaning up the > > onlining+offlining code. > > BTW, I remember that ZONE_DEVICE pages are still required to be set > PG_reserved. That has to be sorted out first. Do they? > I remember that somebody was > working on it a while ago but didn't hear about that again. Will look into > that as well - should be as easy as adding a zone check (if there isn't a > pfn_to_online_page() check already). But of course, there might be special > cases .... I remember Alexander didn't want to change the PageReserved handling because he was worried about unforeseeable side effects. I have a vague recollection he (or maybe Dan) has promissed some follow up clean ups which didn't seem to materialize. -- Michal Hocko SUSE Labs