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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B20EEC433EF for ; Tue, 26 Jul 2022 11:02:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232869AbiGZLC5 (ORCPT ); Tue, 26 Jul 2022 07:02:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231335AbiGZLC4 (ORCPT ); Tue, 26 Jul 2022 07:02:56 -0400 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6BC822F64B for ; Tue, 26 Jul 2022 04:02:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1658833375; x=1690369375; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=UaXM0F/zwS40aBYVOgcSFtmVbNJYu6dxjpf4HXjGGX0=; b=VPPxpawzwFJN2Ca1ilxGiYxHEhHiXhhNI4Fs1ShbQYtMUgQcAOfLE8L3 odQbtdmFzbEPAe6MNdmV3yXxMcjHk3OfVginhgTtEwMn+nqevPODejLMc grAnizLwUsqOVXSbPxa407BInhrEDDkC8iAbgso5oRuWREHtIpGSRQ9On cAAZHb+ccXR7/Rem5nvBdcwN3NqinLjwzvHckxvoHeMbEd43UcX33TApB kMM1RVgoM5DlyEo339LTC6iWK00Fhg4kMlej9S3Jip/yNOG7GMtSio4Cr 0qJeLaaORLML1XZ0YItQvR6SAtShr2C1LlyjhzoFOjo19Vqi5Nj9HP3p7 w==; X-IronPort-AV: E=McAfee;i="6400,9594,10419"; a="270960428" X-IronPort-AV: E=Sophos;i="5.93,193,1654585200"; d="scan'208";a="270960428" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Jul 2022 04:02:54 -0700 X-IronPort-AV: E=Sophos;i="5.93,193,1654585200"; d="scan'208";a="658636813" Received: from lingshan-mobl.ccr.corp.intel.com (HELO [10.249.172.186]) ([10.249.172.186]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Jul 2022 04:02:52 -0700 Message-ID: <9d9d6022-5d49-6f6e-a1ff-562d088ad03c@intel.com> Date: Tue, 26 Jul 2022 19:02:50 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0 Thunderbird/91.11.0 Subject: Re: [PATCH V4 3/6] vDPA: allow userspace to query features of a vDPA device Content-Language: en-US To: Parav Pandit , "jasowang@redhat.com" , "mst@redhat.com" Cc: "virtualization@lists.linux-foundation.org" , "netdev@vger.kernel.org" , "xieyongji@bytedance.com" , "gautam.dawar@amd.com" References: <20220722115309.82746-1-lingshan.zhu@intel.com> <20220722115309.82746-4-lingshan.zhu@intel.com> <6dc2229c-f2f3-017f-16fa-4611e53c774e@intel.com> From: "Zhu, Lingshan" In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 7/24/2022 11:21 PM, Parav Pandit wrote: > >> From: Zhu, Lingshan >> Sent: Saturday, July 23, 2022 7:24 AM >> >> >> On 7/22/2022 9:12 PM, Parav Pandit wrote: >>>> From: Zhu Lingshan >>>> Sent: Friday, July 22, 2022 7:53 AM >>>> >>>> This commit adds a new vDPA netlink attribution >>>> VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES. Userspace can query >> features >>>> of vDPA devices through this new attr. >>>> >>>> Signed-off-by: Zhu Lingshan >>>> --- >>>> drivers/vdpa/vdpa.c | 13 +++++++++---- >>>> include/uapi/linux/vdpa.h | 1 + >>>> 2 files changed, 10 insertions(+), 4 deletions(-) >>>> >>>> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c index >>>> ebf2f363fbe7..9b0e39b2f022 100644 >>>> --- a/drivers/vdpa/vdpa.c >>>> +++ b/drivers/vdpa/vdpa.c >>>> @@ -815,7 +815,7 @@ static int vdpa_dev_net_mq_config_fill(struct >>>> vdpa_device *vdev, static int vdpa_dev_net_config_fill(struct >>>> vdpa_device *vdev, struct sk_buff *msg) { >>>> struct virtio_net_config config = {}; >>>> - u64 features; >>>> + u64 features_device, features_driver; >>>> u16 val_u16; >>>> >>>> vdpa_get_config_unlocked(vdev, 0, &config, sizeof(config)); @@ - >>>> 832,12 +832,17 @@ static int vdpa_dev_net_config_fill(struct >>>> vdpa_device *vdev, struct sk_buff *ms >>>> if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MTU, val_u16)) >>>> return -EMSGSIZE; >>>> >>>> - features = vdev->config->get_driver_features(vdev); >>>> - if (nla_put_u64_64bit(msg, >>>> VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features, >>>> + features_driver = vdev->config->get_driver_features(vdev); >>>> + if (nla_put_u64_64bit(msg, >>>> VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features_driver, >>>> + VDPA_ATTR_PAD)) >>>> + return -EMSGSIZE; >>>> + >>>> + features_device = vdev->config->get_device_features(vdev); >>>> + if (nla_put_u64_64bit(msg, >>>> VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES, >>>> +features_device, >>>> VDPA_ATTR_PAD)) >>>> return -EMSGSIZE; >>>> >>>> - return vdpa_dev_net_mq_config_fill(vdev, msg, features, &config); >>>> + return vdpa_dev_net_mq_config_fill(vdev, msg, features_driver, >>>> +&config); >>>> } >>>> >>>> static int >>>> diff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h >>>> index >>>> 25c55cab3d7c..39f1c3d7c112 100644 >>>> --- a/include/uapi/linux/vdpa.h >>>> +++ b/include/uapi/linux/vdpa.h >>>> @@ -47,6 +47,7 @@ enum vdpa_attr { >>>> VDPA_ATTR_DEV_NEGOTIATED_FEATURES, /* u64 */ >>>> VDPA_ATTR_DEV_MGMTDEV_MAX_VQS, /* u32 */ >>>> VDPA_ATTR_DEV_SUPPORTED_FEATURES, /* u64 */ >>>> + VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES, /* u64 */ >>>> >>> I have answered in previous emails. >>> I disagree with the change. >>> Please reuse VDPA_ATTR_DEV_SUPPORTED_FEATURES. >> I believe we have already discussed this before in the V3 thread. >> I have told you that reusing this attr will lead to a new race condition. >> > Returning attribute cannot lead to any race condition. Please refer to our discussion in the V3 series, I have explained if re-use this attr, it will be a multiple consumers and multiple produces model, it is a typical racing condition. > > >> Pleas refer to the previous thread, and you did not answer my questions in >> that thread. >> >> Thanks, >> Zhu Lingshan >>> MST, >>> I nack this patch. >>> As mentioned in the previous versions, also it is missing the example >> output in the commit log. >>> Please include example output. >>> >>>> VDPA_ATTR_DEV_QUEUE_INDEX, /* u32 */ >>>> VDPA_ATTR_DEV_VENDOR_ATTR_NAME, /* string */ >>>> -- >>>> 2.31.1