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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 BF11CC4338F for ; Mon, 16 Aug 2021 20:54:41 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (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 4AD4460F36 for ; Mon, 16 Aug 2021 20:54:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 4AD4460F36 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 0ECD340360; Mon, 16 Aug 2021 20:54:41 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id gz9fy8tm4Xr9; Mon, 16 Aug 2021 20:54:37 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp2.osuosl.org (Postfix) with ESMTPS id 8402B402F2; Mon, 16 Aug 2021 20:54:36 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 443ABC0010; Mon, 16 Aug 2021 20:54:36 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id E32FCC000E for ; Mon, 16 Aug 2021 20:54:34 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id B1CC8401FC for ; Mon, 16 Aug 2021 20:54:31 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Authentication-Results: smtp4.osuosl.org (amavisd-new); dkim=pass (1024-bit key) header.d=redhat.com Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id qnlRvM85tH2N for ; Mon, 16 Aug 2021 20:54:31 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by smtp4.osuosl.org (Postfix) with ESMTPS id EDF9C401F8 for ; Mon, 16 Aug 2021 20:54:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1629147269; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Mgnd656ubER6m5U6lwnHn022dCGrOqShw0lNJclqLes=; b=c2pfd7gHixL6FWLk+mR55iepFbcsbPB/OUQILRmuQiPQpGNajmclb0F7u5Goijl8GCWKkW JRPRlw4ghPP8dkakPO7nHou2QsrAQDJVfltml75UQ9E4kq/u3+0yu7sQFmdyeGmmzb8GTh 6jepdZFNUOi11xOzO0R3MurSbEqO0HI= Received: from mail-ej1-f69.google.com (mail-ej1-f69.google.com [209.85.218.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-424-d1TwMitTOEiwTUZR2Yyi1g-1; Mon, 16 Aug 2021 16:54:28 -0400 X-MC-Unique: d1TwMitTOEiwTUZR2Yyi1g-1 Received: by mail-ej1-f69.google.com with SMTP id k12-20020a170906680cb02905aeccdbd1efso5170354ejr.9 for ; Mon, 16 Aug 2021 13:54:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=Mgnd656ubER6m5U6lwnHn022dCGrOqShw0lNJclqLes=; b=WqTQhkJ1HP3zP3nh8+uLEzM3hlDD1N5aP1IoJ+D+hkx3SOLqGf0b5/VQlOgnWELnWf Uyf00qGx2hdOuU3QIElsY3TapKvesGY+n9iPNu9JWqRKxZdKpLbuXDFGzfu9tOMKaY/z MqtD1MqUwByxDmpgTvOO34xAXn99UONsmrFumVNL6wfKJ6PGiTHfO0SKYg+TDCMf+KdW MhiuKHO6gjZgOF57OVO8cTYTQgdOvAB5tQecGCPsL3GdzQXWw2BFNvVKVh39XCFYiF03 7MCRmdMJqJ3HGJdzxWeBe2zxzvVG5nUbYdLLY6vaeeCqWtLQVeDPhIKIpRX+sh1ulgQb i8ug== X-Gm-Message-State: AOAM530uLvuXLm8uBBvfsDHEWj+p9t2ihPNHqL0zyjFY+rNXzIsd004+ D96mNPsPqFbXahoJOpXrEykA3Rnywqq/00JnFjpKcE4ngsAV8106Nel5AI9UKQddqEb1F367Dom XMEl47nC1eSNDEHxW+vmvM02u4Tr8JNVtBEfhdTfuKQ== X-Received: by 2002:aa7:c78e:: with SMTP id n14mr38000eds.381.1629147267505; Mon, 16 Aug 2021 13:54:27 -0700 (PDT) X-Google-Smtp-Source: ABdhPJz1mcJKGuG+F8JNEKu5Q5gEnSm6OBT3z0GtsjDRnIC1UDlwaYncAxXdoSRDv75SBMEdCQprzQ== X-Received: by 2002:aa7:c78e:: with SMTP id n14mr37991eds.381.1629147267392; Mon, 16 Aug 2021 13:54:27 -0700 (PDT) Received: from redhat.com ([2.55.150.133]) by smtp.gmail.com with ESMTPSA id q30sm34982edi.84.2021.08.16.13.54.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Aug 2021 13:54:26 -0700 (PDT) Date: Mon, 16 Aug 2021 16:54:23 -0400 From: "Michael S. Tsirkin" To: Parav Pandit Subject: Re: [PATCH linux-next v3 0/6] vdpa: enable user to set mac, mtu Message-ID: <20210816165217-mutt-send-email-mst@kernel.org> References: <20210616191155.102303-1-parav@nvidia.com> <20210805055623-mutt-send-email-mst@kernel.org> <20210806034817-mutt-send-email-mst@kernel.org> <20210809053624-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mst@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Cc: Eli Cohen , "virtualization@lists.linux-foundation.org" X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Mon, Aug 09, 2021 at 09:51:49AM +0000, Parav Pandit wrote: > > From: Michael S. Tsirkin > > Sent: Monday, August 9, 2021 3:10 PM > > > > On Fri, Aug 06, 2021 at 08:55:56AM +0000, Parav Pandit wrote: > > > > > > > > > > > > > > The point is to try and not reinvent a dedicated vpda interface > > > > where a generic one exits. > > > > E.g. for phy things such as mac speed etc, I think most people are > > > > using ethtool things right? > > > > > > As you know vdpa is the backend device for the front-end netdevice > > accessed by the ethtool. > > > vdpa management tool here is composing the vdpa device. > > > > > > For example creator (hypervisor) of the vdpa devices knows that a > > > guest VM is given 4 vcpus, So hypervisor creates a vdpa devices with > > > config space layout as, max_virtqueue_pairs = 4. > > > And the MAC address chosen by hypervisor in mac[6]. > > > > > > Guest VM ethtool can still chose to use less number of channels. > > > > > > Typically, > > > ethtool is for guest VM. > > > vdpa device is in hypevisor. > > > > > > How can hypervisor compose a vdpa device without any tool? > > > How can it tell ethtool, what is supported and what are the defaults? > > > > > > I must be misunderstanding your comment about ethtool. > > > Can you please explain? > > > > > > I am basically saying that we probably want to be able to change MAC of a > > VDPA device on the host without desroying and recreating the device as long > > as it's not in use. > Ok. I understood your comment now. > Yes, this was the objective which is why they are present as independent config knob. > Jason was suggesting to have them as creation only knobs, which requires recreate. > > I don't have strong opinion for either method. > > Passing them at creation time is simpler for user. > If user needs the ability to modify and reuse same device with different config, extending such support in future like this patch should possible. > > So there are two questions to close. > 1. Can we start with config params at vdpa device creation time? I'm not sure whether we need both but I'd like to see a full API and I think we all agree host wants ability to tweak mac after device creation even if guest is not allowed to change mac, right? > 2. Is it ok to have these config params as individual fields at netlink U->K UAPI level? > This is the method proposed in this patch series. > (Similar to incrementally growing vxlan ip link command). > > Or > They should be packed in a structure between U-> K and deal with typecasting based on size and more? > (Jason's input). I'm inclined to say vxlan is closer to a model to follow. -- MST _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization