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 8FC74C61D92 for ; Wed, 22 Nov 2023 07:15:30 +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 C6F382AEE2 for ; Wed, 22 Nov 2023 07:15:29 +0000 (UTC) Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id A70AC9868A2 for ; Wed, 22 Nov 2023 07:15:29 +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 8CA9D9843C0; Wed, 22 Nov 2023 07:15:29 +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 7B2F5986894 for ; Wed, 22 Nov 2023 07:15:29 +0000 (UTC) X-Virus-Scanned: amavisd-new at kavi.com X-MC-Unique: asiJdCCKME2t5rMi9MRYzg-1 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700637326; x=1701242126; 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=NLsoUsHi1WUwIQPPSxQgFZ2CazNavKC1nOUjZ9zgXvA=; b=DbcDT8RWZ6RGA2/OZwjzVwt1GudYJysVImm3UsxA2uuBGVMKCYD4X9ZqCqNEwkX1be F4pcc0oRQJhoRy52hOSHVot4hFpZuJaUaMTQfGQ8Lduc4XjxNaLpUp5lt3mrXnozhBHI omZ8elhX7b0wk8veYw2fswxajxZm94wLKsup2hOEf/H9mx+6liKkqaUzLe8ADy6S5hj5 T0pPbHs8MIDxfGt8kJfvZus9k9+zls46257ypgdOu6LDxurVFoDM7XkqV76RCs6YbXos EMhivdIGNRDyVFsKsZGDbmA2C9/wL728IIml1Qfl5n9W43KsjvLGkHXOU6PuENFCbDu/ AUbQ== X-Gm-Message-State: AOJu0Yy5IGBko/gvd0Ur+5ZbBYEQJrDBZf94JWBPD13k57fIand9+pTd ZCcwxuuOzJyP0Lf8zLdpLOCCdhvK9u9HTN7ZFdgxaEGT4f/nMlNp08nK2KHT/ZMOzP7e8XXQSOy +DCM6IQYbjY+tFNrfobu6HdbRPxNy6xo4Ug== X-Received: by 2002:a05:6402:323:b0:548:5fa2:dcc4 with SMTP id q3-20020a056402032300b005485fa2dcc4mr1147023edw.6.1700637326219; Tue, 21 Nov 2023 23:15:26 -0800 (PST) X-Google-Smtp-Source: AGHT+IErZMYGZIvftgf+oBzYzeCwblzlumhSYt7vE/2c5y9GFYl5gffMVx4W2KNvZl5MArvyBwKUWg== X-Received: by 2002:a05:6402:323:b0:548:5fa2:dcc4 with SMTP id q3-20020a056402032300b005485fa2dcc4mr1147013edw.6.1700637325951; Tue, 21 Nov 2023 23:15:25 -0800 (PST) Date: Wed, 22 Nov 2023 02:15:19 -0500 From: "Michael S. Tsirkin" To: Jason Wang Cc: Parav Pandit , "Zhu, Lingshan" , "eperezma@redhat.com" , "cohuck@redhat.com" , "stefanha@redhat.com" , "virtio-comment@lists.oasis-open.org" Message-ID: <20231122015435-mutt-send-email-mst@kernel.org> References: <4201d1df-100d-495c-97ba-7efbe73d9137@intel.com> <166b43a5-b301-486f-9cc4-01a1cc80eed4@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 V2 4/6] virtio-pci: implement VIRTIO_F_QUEUE_STATE On Wed, Nov 22, 2023 at 12:15:44PM +0800, Jason Wang wrote: > On Wed, Nov 22, 2023 at 12:26 AM Parav Pandit wrote: > > > > > > > From: Jason Wang > > > Sent: Tuesday, November 21, 2023 10:01 AM > > > > > > On Fri, Nov 17, 2023 at 6:06 PM Parav Pandit wrote: > > > > > > > > > > [...] > > > > > Sorry, no virtio specification does not support device migration today. > > > > Nothing is broken by adding new features. > > > > > > > > Above [1] has the right proposal that Jason's paper pointed out. Please use > > > it. > > > > > > I was involved in the design in [1]. And I don't see a connection to the > > > dicussion here > > > > > > 1) It is based on vDPA in L0 > > > 2) It doesn't address the nesting issue, it requires a proper design in the virtio > > > spec to support migration in the nesting layer. > > > > Nothing prevents [1] to be done without vdpa. > > Well, Qemu has SR-IOV emulation for IGB. What's the point of the above > reply? If a hypervisor wishes, it can be done with any device on L0. > > We discuss the possibility of migrating nested VMs, not the > possibility of emulating SR-IOV, no? > > Thanks It depends really. If the way to support nesting is to emulate sr-iov then the question becomes how hard it is to emulate sriov to the point where nesting works. The fact that current hypervisors pretend that a VF is a PF when passing things on to guest and things still seem to work is nice but it's not a hugely important design point IMHO. -- 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. Subscribe: virtio-comment-subscribe@lists.oasis-open.org Unsubscribe: virtio-comment-unsubscribe@lists.oasis-open.org List help: virtio-comment-help@lists.oasis-open.org List archive: https://lists.oasis-open.org/archives/virtio-comment/ Feedback License: https://www.oasis-open.org/who/ipr/feedback_license.pdf List Guidelines: https://www.oasis-open.org/policies-guidelines/mailing-lists Committee: https://www.oasis-open.org/committees/virtio/ Join OASIS: https://www.oasis-open.org/join/