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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,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 132B7C10F0E for ; Tue, 9 Apr 2019 12:13:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C530E20883 for ; Tue, 9 Apr 2019 12:13:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="uYWG8C9f" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727153AbfDIMNT (ORCPT ); Tue, 9 Apr 2019 08:13:19 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:51870 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726388AbfDIMNT (ORCPT ); Tue, 9 Apr 2019 08:13:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=VRvsXTQ3GjdpdN5n2kYCn2enLOEYsHiI8Nby7QD3k1k=; b=uYWG8C9fa2W/1ofQ/6IyFNpSO iu0V82Kq9jQiAgCdfjkjKw22uXQPkJMHiYDnFmiTPazLx6S1iUbd6O2uU8UWQKigb3LKxiuwwUlgJ es8/g9LVDGAPfERmZO5jE5hTxgoi6XD/ZKl4vUm6HU9Vgn7BVC8C9//Jky9Rgcs6wTYggR6JnbTeq MWCyz+g4viZ43BaZzTYSyJxJllb79/Tb/Qe67urnB/U0sXvBsdb/B9KDgv50dFC/hm4lv0N0KOBtn Jnyy1hwkXfhvsJ+jySxvJjcVAg8i8swVl0wtetpC1Sf3TQPK9jPuJvRD0I0ZclNbO36pE9UmYfddb BR/4NS4NQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1hDpcs-0000al-IJ; Tue, 09 Apr 2019 12:13:18 +0000 Date: Tue, 9 Apr 2019 05:13:18 -0700 From: Christoph Hellwig To: Dan Williams Cc: linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , Len Brown , Keith Busch , Jonathan Cameron , vishal.l.verma@intel.com, x86@kernel.org, linux-mm@kvack.org, linux-nvdimm@lists.01.org Subject: Re: [RFC PATCH 4/5] acpi/hmat: Register special purpose memory as a device Message-ID: <20190409121318.GA16955@infradead.org> References: <155440490809.3190322.15060922240602775809.stgit@dwillia2-desk3.amr.corp.intel.com> <155440492988.3190322.4475460421334178449.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <155440492988.3190322.4475460421334178449.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 04, 2019 at 12:08:49PM -0700, Dan Williams wrote: > Memory that has been tagged EFI_SPECIAL_PURPOSE, and has performance > properties described by the ACPI HMAT is expected to have an application > specific consumer. > > Those consumers may want 100% of the memory capacity to be reserved from > any usage by the kernel. By default, with this enabling, a platform > device is created to represent this differentiated resource. This sounds more than weird. Since when did we let the firmware decide who can use the memory?