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=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 3A3FDC3276C for ; Fri, 3 Jan 2020 02:09:06 +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 B421C222C3 for ; Fri, 3 Jan 2020 02:09:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B421C222C3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=us.ibm.com 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 47ppHK47rrzDqCK for ; Fri, 3 Jan 2020 13:09:01 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=us.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=linuxram@us.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=us.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 47ppF65J3DzDq9L for ; Fri, 3 Jan 2020 13:07:06 +1100 (AEDT) Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 00322OEg085352 for ; Thu, 2 Jan 2020 21:07:02 -0500 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0a-001b2d01.pphosted.com with ESMTP id 2x88jwhm54-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 02 Jan 2020 21:07:02 -0500 Received: from localhost by e06smtp01.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 3 Jan 2020 02:06:57 -0000 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 00326t7C54591496 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 3 Jan 2020 02:06:55 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 566EE11C05E; Fri, 3 Jan 2020 02:06:55 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7BBE311C066; Fri, 3 Jan 2020 02:06:53 +0000 (GMT) Received: from oc0525413822.ibm.com (unknown [9.80.213.131]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Fri, 3 Jan 2020 02:06:53 +0000 (GMT) Date: Thu, 2 Jan 2020 18:06:50 -0800 From: Ram Pai To: David Gibson References: <20191216041924.42318-1-aik@ozlabs.ru> <20191216041924.42318-5-aik@ozlabs.ru> <20200102222106.GB5556@oc0525413822.ibm.com> <20200103000849.GL2098@umbus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200103000849.GL2098@umbus> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 20010302-4275-0000-0000-000003943CC5 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20010302-4276-0000-0000-000038A82092 Message-Id: <20200103020650.GE5556@oc0525413822.ibm.com> Subject: RE: [PATCH kernel v2 4/4] powerpc/pseries/svm: Allow IOMMU to work in SVM X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2020-01-02_08:2020-01-02,2020-01-02 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=753 mlxscore=0 impostorscore=0 clxscore=1015 bulkscore=0 adultscore=0 spamscore=0 malwarescore=0 priorityscore=1501 suspectscore=18 phishscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-2001030018 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: , Reply-To: Ram Pai Cc: Alexey Kardashevskiy , Michael Anderson , kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Thiago Jung Bauermann Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, Jan 03, 2020 at 11:08:49AM +1100, David Gibson wrote: > On Thu, Jan 02, 2020 at 02:21:06PM -0800, Ram Pai wrote: > > On Mon, Dec 16, 2019 at 03:19:24PM +1100, Alexey Kardashevskiy wrote: > > > H_PUT_TCE_INDIRECT uses a shared page to send up to 512 TCE to > > > a hypervisor in a single hypercall. > > > > Actually H_PUT_TCE_INDIRECT never used shared page. It would have > > used shared pages if the 'shared-page' solution was accepted. :) > > Well, it depends what you mean by "shared". In the non-PEF case we do > use a shared page in the sense that it is accessed by both guest and > hypervisor. It's just not shared in the PEF sense. Ah..I see. That sentence can be right or wrong based on the reader's interpretion of the phrase 'shared page'. To me a 'shared page' is a page that is **explicitly** shared with the hypervisor. However I can see 'shared page' to mean a page that is simply shared; either implicitly or explicitly. Given that, there is a possibility for mis-interpretation, I think, it might be better to avoid the phrase 'shared page' if possible. > > > > This does not work for secure VMs > > > as the page needs to be shared or the VM should use H_PUT_TCE instead. > > > > Maybe you should say something like this.. ? > > > > H_PUT_TCE_INDIRECT does not work for secure VMs, since the page > > containing the TCE entries is not accessible to the hypervisor. > > > > > ..snip. -- Ram Pai