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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 D1AD1C43603 for ; Mon, 9 Dec 2019 20:47:52 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8B84B20637 for ; Mon, 9 Dec 2019 20:47:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8B84B20637 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 47WwHp4dKnzDqSC for ; Tue, 10 Dec 2019 07:47:50 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 47WwCF5vx4zDqQM for ; Tue, 10 Dec 2019 07:43:52 +1100 (AEDT) Received: by verein.lst.de (Postfix, from userid 2407) id 69ADB68BE1; Mon, 9 Dec 2019 21:43:45 +0100 (CET) Date: Mon, 9 Dec 2019 21:43:45 +0100 From: Christoph Hellwig To: Logan Gunthorpe Subject: Re: [PATCH 0/6] Allow setting caching mode in arch_add_memory() for P2PDMA Message-ID: <20191209204345.GA29265@lst.de> References: <20191209191346.5197-1-logang@deltatee.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191209191346.5197-1-logang@deltatee.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org, Andrew Morton , Will Deacon , linux-sh@vger.kernel.org, Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-mm@kvack.org, Ingo Molnar , Thomas Gleixner , Andy Lutomirski , Borislav Petkov , Dan Williams , linuxppc-dev@lists.ozlabs.org, Christoph Hellwig , linux-arm-kernel@lists.infradead.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Dec 09, 2019 at 12:13:40PM -0700, Logan Gunthorpe wrote: > This changes is pretty routine for most of the arches: x86_64, s390, arm64 > and powerpc simply need to thread the pgprot through to where the page tables > are setup. x86_32 unfortunately sets up the page tables at boot so > must use _set_memory_prot() to change their caching mode. ia64 and sh > don't appear to have an easy way to change the page tables so, for now > at least, we just return -EINVAL on such mappings and thus they will > not support P2PDMA memory until the work for this is done. ia64 and sh don't support ZONE_DEVICE mappings anyway as far as I know. This generally looks fine to me.