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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 0C772C433DF for ; Tue, 2 Jun 2020 05:15:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D0B4F20734 for ; Tue, 2 Jun 2020 05:15:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="IMukX3sO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726007AbgFBFPW (ORCPT ); Tue, 2 Jun 2020 01:15:22 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:42441 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725841AbgFBFPV (ORCPT ); Tue, 2 Jun 2020 01:15:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591074920; 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=Omt9gJipjlxk0xAiBkDipMLYpK/jCtWILzTzD1eFi2g=; b=IMukX3sOMlM8mgpuDBgEJx7qRf7dV6flhp4QzdZOJqHVfHbzK6nzzOZWIZwPmaA1ERyUMZ xZkdHXhr8FDX1cxfedAp1VGBp1VNI4cSze6y8E4cG3yLSZujyi2z07heo3SgCLfy8qxxG4 4y5VuwtYiW15TQRz1ND4sbDy7VDFUto= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-320-WN6aMau5OVWM74m0XJzd1w-1; Tue, 02 Jun 2020 01:09:38 -0400 X-MC-Unique: WN6aMau5OVWM74m0XJzd1w-1 Received: by mail-wr1-f70.google.com with SMTP id m14so881215wrj.12 for ; Mon, 01 Jun 2020 22:09:38 -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=Omt9gJipjlxk0xAiBkDipMLYpK/jCtWILzTzD1eFi2g=; b=fKWyfxtqjPQcoZ1vE5FSO4vAQ7HmJTYlfmk2jE0lZ+mI7lEp87LBSyllluS0Nt3R0P FmrpsJHdv7c4EfGZpHdCmvsQ7yI/yEB8w9CehPo9GFcKjE9GeBFw1IMB5qna4wQH2yly t/c26Y8DTAZirpNM08kJaJgnGMxvNopM76Visfho7sNcRnKLDlt5iopwjRLsLixbhqpF koeE1Ms2xzSvqGirGN5rA3X7Xhi2dDk6VXdbs15+DGr+h/A82kv1t4o1vfOXLGEjywoB aedgbl1I7X5vreLQspQGD4CUp2/cuMhfkZcnUkv9Nu7cY6BegutW9FY9LniC038XGIwB oKxg== X-Gm-Message-State: AOAM530R6OjIwiucbT5BA4DDZQInjTkRWYfJo7HhJv1z8ByI9zNr0wR5 0mGe7NIWTDF/QszjNexHJqg0eP45nWWyHnkokVAc92juLc/TRb3saW7YQjDh7vomXRQtHVjn2Ll 4jwVKZItTGhP7IT1DFHaD3zao X-Received: by 2002:a05:6000:11cd:: with SMTP id i13mr23481643wrx.141.1591074577588; Mon, 01 Jun 2020 22:09:37 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzC4LVeDOhERR8qf9AS4nc4Mi6WpaPRsevGBTu/GWRHQywd6PHu2y8E93bGd9V5IBqDeftUgQ== X-Received: by 2002:a05:6000:11cd:: with SMTP id i13mr23481639wrx.141.1591074577444; Mon, 01 Jun 2020 22:09:37 -0700 (PDT) Received: from redhat.com (bzq-109-64-41-91.red.bezeqint.net. [109.64.41.91]) by smtp.gmail.com with ESMTPSA id a3sm1785369wmb.7.2020.06.01.22.09.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 01 Jun 2020 22:09:36 -0700 (PDT) Date: Tue, 2 Jun 2020 01:09:34 -0400 From: "Michael S. Tsirkin" To: Jason Wang Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, rob.miller@broadcom.com, lingshan.zhu@intel.com, eperezma@redhat.com, lulu@redhat.com, shahafs@mellanox.com, hanand@xilinx.com, mhabets@solarflare.com, gdawar@xilinx.com, saugatm@xilinx.com, vmireyno@marvell.com, zhangweining@ruijie.com.cn, eli@mellanox.com Subject: Re: [PATCH 5/6] vdpa: introduce virtio pci driver Message-ID: <20200602010809-mutt-send-email-mst@kernel.org> References: <20200529080303.15449-1-jasowang@redhat.com> <20200529080303.15449-6-jasowang@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200529080303.15449-6-jasowang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 29, 2020 at 04:03:02PM +0800, Jason Wang wrote: > Note that since virtio specification does not support get/restore > virtqueue state. So we can not use this driver for VM. This can be > addressed by extending the virtio specification. Looks like exactly the kind of hardware limitation VDPA is supposed to paper over within guest. So I suggest we use this as a litmus test, and find ways for VDPA to handle this without spec changes. -- MST