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 7A11BCA0EC3 for ; Tue, 12 Sep 2023 10:27:48 +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 EF8A9C8C4F for ; Tue, 12 Sep 2023 10:27:47 +0000 (UTC) Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id DBAA79864A4 for ; Tue, 12 Sep 2023 10:27:47 +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 D0139986490; Tue, 12 Sep 2023 10:27:47 +0000 (UTC) Mailing-List: contact virtio-dev-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 BC21898648C; Tue, 12 Sep 2023 10:27:43 +0000 (UTC) X-Virus-Scanned: amavisd-new at kavi.com X-IronPort-AV: E=McAfee;i="6600,9927,10830"; a="358610576" X-IronPort-AV: E=Sophos;i="6.02,139,1688454000"; d="scan'208";a="358610576" X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10830"; a="720350704" X-IronPort-AV: E=Sophos;i="6.02,139,1688454000"; d="scan'208";a="720350704" Message-ID: <4c4c2478-c90b-fb5b-cc06-bc74293862b9@intel.com> Date: Tue, 12 Sep 2023 18:27:17 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Firefox/102.0 Thunderbird/102.15.0 Content-Language: en-US To: Parav Pandit , Jason Wang Cc: "Michael S. Tsirkin" , "eperezma@redhat.com" , "cohuck@redhat.com" , "stefanha@redhat.com" , "virtio-comment@lists.oasis-open.org" , "virtio-dev@lists.oasis-open.org" References: <20230906081637.32185-1-lingshan.zhu@intel.com> <20230906081637.32185-6-lingshan.zhu@intel.com> <20230906043016-mutt-send-email-mst@kernel.org> <7cc22be6-f984-ba53-5979-0306a118a6df@intel.com> <5449424a-4872-0164-0c3f-caa34ad46388@intel.com> From: "Zhu, Lingshan" In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: [virtio-dev] Re: [virtio-comment] [PATCH 5/5] virtio-pci: implement VIRTIO_F_QUEUE_STATE On 9/12/2023 3:43 PM, Parav Pandit wrote: >> From: Zhu, Lingshan >> Sent: Tuesday, September 12, 2023 1:06 PM >> >> On 9/12/2023 2:52 PM, Parav Pandit wrote: >>>> From: Zhu, Lingshan >>>> Sent: Tuesday, September 12, 2023 12:13 PM Why need P2P for Live >>>> Migration? >>> A peer device may be accessing the virtio device. Hence first all the devices to >> be stopped like [1] allowing them to accept driver notifications from the peer >> device. >>> Once all the devices are stopped, than each device to be freeze to not do any >> device context updates. At this point the final device context can be read by the >> owner driver. >> Is it beyond the spec? Nvidia specific use case and not related to virtio live >> migration? > Not at all Nvidia specific. > And not all at all beyond the specification. > PCI transport is probably by far most common transport of virtio. > And hence, spec proposed in [1] covers it. > > It is the base line implementation of leading OS such as Linux kernel. > > Decade mature stack like vfio recommends support for p2p as base line without which multiple devices migration can fail as hypervisor has no knowledge if two devices are interacting or not. > > [1] https://lists.oasis-open.org/archives/virtio-comment/202309/msg00071.html still, why do you think P2P is a concern of live migration? Or why do you think Live Migration should implement special support for P2P? --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org