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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 450F3104951B for ; Wed, 11 Mar 2026 09:39:28 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1w0G1u-0000NP-FR; Wed, 11 Mar 2026 05:39:02 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1w0G1s-0000N0-6d for qemu-devel@nongnu.org; Wed, 11 Mar 2026 05:39:01 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1w0G1q-00042G-J2 for qemu-devel@nongnu.org; Wed, 11 Mar 2026 05:38:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1773221936; 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=GPENB8X/GGkKQtJ22NqgJPvhCO6a4eylY2lA9lTt7Ss=; b=TWSspABVI+d6mBbY61S+zDySuVlwkGfDfebOGeyPSb7Wllm8ommpG5b2TztOmMc6Q31j2O i5z7CafwlkIGNJKM47zhSq+hYlrK/u5Eezr/anjZTyEqcTiQ57U+043XEupXJAMp79wUYJ og8SN9iDtfZDMEknHDYJlAfRx14Any0= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-611-J-UK2zjWNdO_7Ak6hbKVkA-1; Wed, 11 Mar 2026 05:38:52 -0400 X-MC-Unique: J-UK2zjWNdO_7Ak6hbKVkA-1 X-Mimecast-MFC-AGG-ID: J-UK2zjWNdO_7Ak6hbKVkA_1773221931 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 79FCA18005BE; Wed, 11 Mar 2026 09:38:50 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.45.242.12]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 3380418001FE; Wed, 11 Mar 2026 09:38:49 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id D079021E681E; Wed, 11 Mar 2026 10:38:46 +0100 (CET) From: Markus Armbruster To: Vladimir Sementsov-Ogievskiy Cc: jasowang@redhat.com, mst@redhat.com, thuth@redhat.com, eblake@redhat.com, farosas@suse.de, peterx@redhat.com, zhao1.liu@intel.com, wangyanan55@huawei.com, philmd@linaro.org, marcel.apfelbaum@gmail.com, eduardo@habkost.net, davydov-max@yandex-team.ru, qemu-devel@nongnu.org, yc-core@yandex-team.ru, leiyang@redhat.com, raphael.s.norwitz@gmail.com, bchaney@akamai.com Subject: Re: [PATCH v12 6/8] net/tap: support local migration with virtio-net In-Reply-To: <3408f5b9-d0b8-4005-853c-119b2b429829@yandex-team.ru> (Vladimir Sementsov-Ogievskiy's message of "Tue, 10 Mar 2026 18:42:53 +0300") References: <20260306213235.216863-1-vsementsov@yandex-team.ru> <20260306213235.216863-7-vsementsov@yandex-team.ru> <87jyvjiypw.fsf@pond.sub.org> <3408f5b9-d0b8-4005-853c-119b2b429829@yandex-team.ru> Date: Wed, 11 Mar 2026 10:38:46 +0100 Message-ID: <87bjgueme1.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -3 X-Spam_score: -0.4 X-Spam_bar: / X-Spam_report: (-0.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.819, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.903, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Vladimir Sementsov-Ogievskiy writes: > On 10.03.26 16:46, Markus Armbruster wrote: >> Vladimir Sementsov-Ogievskiy writes: >> >>> Support transferring of TAP state (including open fd) through >>> migration stream as part of viritio-net "local-migration". >>> >>> Add new option, incoming-fds, which should be set to true to >>> trigger new logic. >>> >>> For new option require explicitly unset script and downscript, >>> to keep possibility of implementing support for them in future. >>> >>> Signed-off-by: Vladimir Sementsov-Ogievskiy >> [...] >> >>> diff --git a/qapi/net.json b/qapi/net.json >>> index 118bd349651..79f5ce9f431 100644 >>> --- a/qapi/net.json >>> +++ b/qapi/net.json >>> @@ -355,6 +355,9 @@ >>> # @poll-us: maximum number of microseconds that could be spent on busy >>> # polling for tap (since 2.7) >>> # >>> +# @incoming-fds: do not open/connnect any resources, instead wait for >>> +# TAP state from incoming migration stream. (Since 11.0) >> "resources"? The name @incoming-fds suggests this is about file >> descriptors... > > Hmm. But, I can't say "open any file descriptors".. > > >> "wait for TAP state from" does not make sense. Do you mean "retrieve >> TAP state from"? > > Retrieve means actively do something, but I mean, that FDs will come in > future from incoming migration stream, and we just wait for it and "do nothing" > at the moment of net-tap initialization. > > > Let me try to reword: > > Do not open or create any TAP devices. Prepare for getting opened > TAP file descriptors from incoming migration stream. Better, thanks! >> Is any part of NetdevTapOptions ignored when @incoming-fds is true? > > Hmm yes. sndbuf, vnet_hdr and ifname. I should add this information here. I dislike ignoring the user's instructions silently. Can we make it an error? [...]