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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 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 47854C4BA12 for ; Wed, 26 Feb 2020 15:37:08 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 0AF29206E6 for ; Wed, 26 Feb 2020 15:37:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0AF29206E6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:45990 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j6ykF-0002hc-9T for qemu-devel@archiver.kernel.org; Wed, 26 Feb 2020 10:37:07 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:53815) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j6yje-0002Fo-22 for qemu-devel@nongnu.org; Wed, 26 Feb 2020 10:36:33 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j6yja-0003BA-Jm for qemu-devel@nongnu.org; Wed, 26 Feb 2020 10:36:30 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:37956) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j6yja-00038p-Cc for qemu-devel@nongnu.org; Wed, 26 Feb 2020 10:36:26 -0500 Received: from pps.filterd (m0187473.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01QFZrxr129721 for ; Wed, 26 Feb 2020 10:36:25 -0500 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ydh919b52-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 26 Feb 2020 10:36:25 -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) Wed, 26 Feb 2020 15:36:20 -0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01QFaJa540567004 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 26 Feb 2020 15:36:19 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A4BEAAE055; Wed, 26 Feb 2020 15:36:19 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 788F2AE057; Wed, 26 Feb 2020 15:36:19 +0000 (GMT) Received: from oc2783563651 (unknown [9.152.224.149]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Wed, 26 Feb 2020 15:36:19 +0000 (GMT) Date: Wed, 26 Feb 2020 16:36:18 +0100 From: Halil Pasic To: "Michael S. Tsirkin" Subject: Re: [PATCH V2] vhost: correctly turn on VIRTIO_F_IOMMU_PLATFORM In-Reply-To: <20200226083654-mutt-send-email-mst@kernel.org> References: <20200226094357.25061-1-jasowang@redhat.com> <20200226142839.4263de9b.pasic@linux.ibm.com> <20200226083654-mutt-send-email-mst@kernel.org> Organization: IBM X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 20022615-4275-0000-0000-000003A5B269 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20022615-4276-0000-0000-000038B9CB21 Message-Id: <20200226163618.31aa86ed.pasic@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.572 definitions=2020-02-26_05:2020-02-26, 2020-02-26 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 spamscore=0 malwarescore=0 priorityscore=1501 lowpriorityscore=0 impostorscore=0 mlxlogscore=913 adultscore=0 bulkscore=0 mlxscore=0 suspectscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002260110 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] X-Received-From: 148.163.156.1 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jason Wang , qemu-devel@nongnu.org, qemu-stable@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, 26 Feb 2020 08:37:13 -0500 "Michael S. Tsirkin" wrote: > On Wed, Feb 26, 2020 at 02:28:39PM +0100, Halil Pasic wrote: > > On Wed, 26 Feb 2020 17:43:57 +0800 > > Jason Wang wrote: > > > > > We turn on device IOTLB via VIRTIO_F_IOMMU_PLATFORM unconditionally on > > > platform without IOMMU support. This can lead unnecessary IOTLB > > > transactions which will damage the performance. > > > > > > Fixing this by check whether the device is backed by IOMMU and disable > > > device IOTLB. > > > > > > Reported-by: Halil Pasic > > > Fixes: c471ad0e9bd46 ("vhost_net: device IOTLB support") > > > Cc: qemu-stable@nongnu.org > > > Signed-off-by: Jason Wang > > > > Tested-by: Halil Pasic > > Reviewed-by: Halil Pasic > > > > Thank you very much for fixing this! BTW as I mentioned before it > > fixes vhost-vsock with iommu_platform=on as well. > > Fixes as in improves performance? No, fixes like one does not get something like: qemu-system-s390x: vhost_set_features failed: Operation not supported (95) qemu-system-s390x: Error starting vhost: 95 any more. Regards, Halil [..]