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=-8.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 C900FC433DF for ; Tue, 4 Aug 2020 23:22:58 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 9DD4A2073E for ; Tue, 4 Aug 2020 23:22:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="UqSjPVKu" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9DD4A2073E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k36GN-0001g6-HI; Tue, 04 Aug 2020 23:22:31 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k36GM-0001g1-Oo for xen-devel@lists.xenproject.org; Tue, 04 Aug 2020 23:22:30 +0000 X-Inumbo-ID: 1b6332ac-f65e-4ebd-8dbb-081a2cc29d21 Received: from mail.kernel.org (unknown [198.145.29.99]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 1b6332ac-f65e-4ebd-8dbb-081a2cc29d21; Tue, 04 Aug 2020 23:22:29 +0000 (UTC) Received: from localhost (c-67-164-102-47.hsd1.ca.comcast.net [67.164.102.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D85C92073E; Tue, 4 Aug 2020 23:22:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596583348; bh=PsSJUCD59asltcoFiaVL865acSKkt2G4DHIVsCjUDOs=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=UqSjPVKuhrcyUhuZlqz/uf2//X+bnHxeXL4pwtRu1HNLEEmeQB+NkDAlTPcLo06NQ ZHdk9Zd9pmuO9R20Hjg1tkml5QRywe8TzUJQy/QyZ0g59UDiv9CPwsgUtVv4GOfvEN fylxSKRjtfeABEWpflj9Vb6/xD/R8KGc1B2s2tNI= Date: Tue, 4 Aug 2020 16:22:27 -0700 (PDT) From: Stefano Stabellini X-X-Sender: sstabellini@sstabellini-ThinkPad-T480s To: Julien Grall Subject: Re: [RFC PATCH V1 04/12] xen/arm: Introduce arch specific bits for IOREQ/DM features In-Reply-To: <6c4f7698-a015-91c7-83ec-203f63d48900@xen.org> Message-ID: References: <1596478888-23030-1-git-send-email-olekstysh@gmail.com> <1596478888-23030-5-git-send-email-olekstysh@gmail.com> <001101d66a33$bba44670$32ecd350$@xen.org> <6c4f7698-a015-91c7-83ec-203f63d48900@xen.org> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: 'Stefano Stabellini' , 'Wei Liu' , paul@xen.org, 'Andrew Cooper' , 'Ian Jackson' , 'George Dunlap' , 'Oleksandr Tyshchenko' , 'Oleksandr Tyshchenko' , 'Julien Grall' , 'Jan Beulich' , xen-devel@lists.xenproject.org, 'Daniel De Graaf' , 'Volodymyr Babchuk' Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" On Tue, 4 Aug 2020, Julien Grall wrote: > On 04/08/2020 08:49, Paul Durrant wrote: > > > diff --git a/tools/libxc/xc_dom_arm.c b/tools/libxc/xc_dom_arm.c > > > index 931404c..b5fc066 100644 > > > --- a/tools/libxc/xc_dom_arm.c > > > +++ b/tools/libxc/xc_dom_arm.c > > > @@ -26,11 +26,19 @@ > > > #include "xg_private.h" > > > #include "xc_dom.h" > > > > > > -#define NR_MAGIC_PAGES 4 > > > + > > > #define CONSOLE_PFN_OFFSET 0 > > > #define XENSTORE_PFN_OFFSET 1 > > > #define MEMACCESS_PFN_OFFSET 2 > > > #define VUART_PFN_OFFSET 3 > > > +#define IOREQ_SERVER_PFN_OFFSET 4 > > > + > > > +#define NR_IOREQ_SERVER_PAGES 8 > > > +#define NR_MAGIC_PAGES (4 + NR_IOREQ_SERVER_PAGES) > > > + > > > +#define GUEST_MAGIC_BASE_PFN (GUEST_MAGIC_BASE >> XC_PAGE_SHIFT) > > > + > > > +#define special_pfn(x) (GUEST_MAGIC_BASE_PFN + (x)) > > > > Why introduce 'magic pages' for Arm? It's quite a horrible hack that we have > > begun to do away with by adding resource mapping. > > This would require us to mandate at least Linux 4.17 in a domain that will run > an IOREQ server. If we don't mandate this, the minimum version would be 4.10 > where DM OP was introduced. > > Because of XSA-300, we could technically not safely run an IOREQ server with > existing Linux. So it is probably OK to enforce the use of the acquire > interface. +1