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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 8D0B2C43387 for ; Thu, 17 Jan 2019 16:29:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 553A220851 for ; Thu, 17 Jan 2019 16:29:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728792AbfAQQ3N (ORCPT ); Thu, 17 Jan 2019 11:29:13 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47842 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728562AbfAQQ3N (ORCPT ); Thu, 17 Jan 2019 11:29:13 -0500 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 22911804F8; Thu, 17 Jan 2019 16:29:13 +0000 (UTC) Received: from segfault.boston.devel.redhat.com (segfault.boston.devel.redhat.com [10.19.60.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9CD1C60933; Thu, 17 Jan 2019 16:29:11 +0000 (UTC) From: Jeff Moyer To: Dave Hansen Cc: dave@sr71.net, thomas.lendacky@amd.com, mhocko@suse.com, linux-nvdimm@lists.01.org, tiwai@suse.de, ying.huang@intel.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, bp@suse.de, baiyaowei@cmss.chinamobile.com, zwisler@kernel.org, bhelgaas@google.com, fengguang.wu@intel.com, akpm@linux-foundation.org Subject: Re: [PATCH 0/4] Allow persistent memory to be used like normal RAM References: <20190116181859.D1504459@viggo.jf.intel.com> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 Date: Thu, 17 Jan 2019 11:29:10 -0500 In-Reply-To: <20190116181859.D1504459@viggo.jf.intel.com> (Dave Hansen's message of "Wed, 16 Jan 2019 10:18:59 -0800") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Thu, 17 Jan 2019 16:29:13 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dave Hansen writes: > Persistent memory is cool. But, currently, you have to rewrite > your applications to use it. Wouldn't it be cool if you could > just have it show up in your system like normal RAM and get to > it like a slow blob of memory? Well... have I got the patch > series for you! So, isn't that what memory mode is for? https://itpeernetwork.intel.com/intel-optane-dc-persistent-memory-operating-modes/ Why do we need this code in the kernel? -Jeff