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 ws5-mx01.kavi.com (ws5-mx01.kavi.com [34.193.7.191]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4E2ECCDB47E for ; Fri, 13 Oct 2023 13:50:32 +0000 (UTC) Received: from lists.oasis-open.org (oasis.ws5.connectedcommunity.org [10.110.1.242]) by ws5-mx01.kavi.com (Postfix) with ESMTP id 919063357E for ; Fri, 13 Oct 2023 13:50:31 +0000 (UTC) Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 69351986844 for ; Fri, 13 Oct 2023 13:50:31 +0000 (UTC) Received: from host09.ws5.connectedcommunity.org (host09.ws5.connectedcommunity.org [10.110.1.97]) by lists.oasis-open.org (Postfix) with QMQP id 494F2986837; Fri, 13 Oct 2023 13:50:31 +0000 (UTC) Mailing-List: contact virtio-comment-help@lists.oasis-open.org; run by ezmlm List-ID: Sender: Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 71805986838 for ; Fri, 13 Oct 2023 13:49:30 +0000 (UTC) X-Virus-Scanned: amavisd-new at kavi.com X-MC-Unique: V7272XvTNg-w_yvX6It3xw-1 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697204967; x=1697809767; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Hadox0Q4BUlSLtcHnzKV22LC+E8Eg8jT6juzgT+H4rE=; b=EC9QzQ8a+pmifYQYfA/Nj00IRnHitSU5lPkRCMSAgXVU0S/pYkEAP9dtTQv1YZvCY3 f/O29CYmNS4RZ5zY1D9jwGT4pBEfnGD59I+uRCsRqlJ+zTVZGAu2GoUnnV1XxNnD+nxF OV7S7AWucTbr6aRS7HGPtikD8/oYnAPZ11pNTaWZejAyaXgxz7oPITvBDZ5bJH1YkLul u1SIct4VkYqXbdpTtY5zAICVQLYkyxxTxrG7MHYQw+xSGIoIZq3uRLIgKjZZBZDH300w 36/M7Zer5m18vVurxrdMIleNBEsl5nblz3Seo1SkrEhYBiMrQ+2pullfFObzQXx3ZGS2 9izA== X-Gm-Message-State: AOJu0YxIigpIhkR50s544ijVEyrFTbr76DC1zY0fG1Sn0DWJtnFsibzC lKEx7Ib4gM+yLnZNXWaindLLRgNEiCGOPuY5itNmxIEPZgoSjCTNizb8M1hPlxvr/hpquNcvYVM wBa7aR/kl0JlF/J2xNcKF5IHlj2rXcAU4+w== X-Received: by 2002:a5d:4388:0:b0:32d:9755:44f1 with SMTP id i8-20020a5d4388000000b0032d975544f1mr2742817wrq.32.1697204967152; Fri, 13 Oct 2023 06:49:27 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFjUKNl47iMXDwAkYbWAtRxswUPiO6YlG5xDyy3MbdCwBrQI1whn7CoNg6tpo3Oda38jidgnQ== X-Received: by 2002:a5d:4388:0:b0:32d:9755:44f1 with SMTP id i8-20020a5d4388000000b0032d975544f1mr2742797wrq.32.1697204966785; Fri, 13 Oct 2023 06:49:26 -0700 (PDT) Date: Fri, 13 Oct 2023 09:49:21 -0400 From: "Michael S. Tsirkin" To: "Zhu, Lingshan" Cc: Parav Pandit , Jason Wang , "virtio-comment@lists.oasis-open.org" , "cohuck@redhat.com" , "sburla@marvell.com" , Shahaf Shuler , Maor Gottlieb , Yishai Hadas Message-ID: <20231013093939-mutt-send-email-mst@kernel.org> References: <85c59856-b68e-940c-08ed-a14e5a02554d@intel.com> <6fc4af28-67d9-781b-a243-a6c2ebf0244c@intel.com> MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Subject: Re: [virtio-comment] Re: [PATCH v1 3/8] device-context: Define the device context fields for device migration On Fri, Oct 13, 2023 at 05:44:27PM +0800, Zhu, Lingshan wrote: > > As Michael said, software based nesting is used.. > > See if actual hw based devices can implement it or not. Many components of cpu cannot do N level nesting either, but may be virtio can. > > I don’t know how yet. > two facts: > 1. virito works for nested for years > 2. your admin vq lm solution does not work for nested First virtio works but nested migration doesn't: the way virtio works doesn't allow L1 hypervisor to migrate L2 if it passes virtio through to L2, except by using full emulation approaches such as shadow vq - surely, these are still possible. Second doesn't work is an overstatement. It remains to be seen what else can be done though. You hinted at a depdenency on PASID. Have owner be a PASID and Parav's approach seems to work with little to no change. -- MST This publicly archived list offers a means to provide input to the OASIS Virtual I/O Device (VIRTIO) TC. In order to verify user consent to the Feedback License terms and to minimize spam in the list archive, subscription is required before posting. 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