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 mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF343CA5FC4 for ; Fri, 2 Oct 2026 07:44:52 +0000 (UTC) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id D2B4840144; Fri, 2 Oct 2026 09:44:51 +0200 (CEST) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mails.dpdk.org (Postfix) with ESMTP id 2B4FD4003C for ; Fri, 2 Oct 2026 09:44:50 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1790927089; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OSVIgmXsoMq3jxxqDtCR0T2/MviDhFlVTUJhP4uYWLs=; b=UK1YtCv/5j7CXuSMqifaWwSA43DL/CSw0R/051nxEhANVDavigRQhWL/hxVuq6ZxURDulO 4OK274tVxv+Qnj7HiQ4yEsz1THHvkze4wTB0suvhj7xXoCddfUwO5sPK2zU3irhq5eN7rH Mer7b7XqsA0jty4YHcncBEop2vpQjwY= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-416-NN1YfOMpOWGRhj6SAz3YTA-1; Fri, 02 Oct 2026 03:44:48 -0400 X-MC-Unique: NN1YfOMpOWGRhj6SAz3YTA-1 X-Mimecast-MFC-AGG-ID: NN1YfOMpOWGRhj6SAz3YTA_1790927087 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (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-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E0D97195D00C; Fri, 2 Oct 2026 07:44:46 +0000 (UTC) Received: from dmarchan.redhat.corp (headnet03.pony-001.prod.iad2.dc.redhat.com [10.2.32.114]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id A849C30000E4; Fri, 2 Oct 2026 07:44:45 +0000 (UTC) From: David Marchand To: maxime.coquelin@redhat.com, dev@dpdk.org Cc: bruce.richardson@intel.com Subject: [PATCH v3 0/6] Drop vhost async (DMA-accelerated) datapath Date: Fri, 2 Oct 2026 09:44:34 +0200 Message-ID: <20261002074440.2551536-1-david.marchand@redhat.com> In-Reply-To: <20260723153111.3943368-1-david.marchand@redhat.com> References: <20260723153111.3943368-1-david.marchand@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: JlhV4bhF1Xsg746Qk-UIL14lj9jFTs70kMM32DXDf-g_1790927087 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org The integration of this feature in OVS has been postponed following feedback how the current API forced the complexity on the application side. There is no contributor working on making those changes. The feature has no other identified opensource consumer. On the other hand, this feature has been left unattended for some years now while the "normal" datapath is actively maintained. It is highly likely the async datapath code, which never underwent a stabilisation phase, is riddled with bugs. Given the craziness around finding security bugs with AI, and since the vhost library is a good target, I propose to drop this feature and reduce the library attack surface. There is one complication with the vhost_crypto and some external applications that seemed to rely on the async flag to track and populate guest pages, so a new flag replacing async is added by this series. -- David Marchand Changes since v2: - updated release notes and vhost example documentation, - removed some async statistics missed in previous revisions, - re-added checks on map populate and post copy or other virtio features, Changes since v1: - removed unneeded dependencies on the PCI library, Changes since RFC: - maintained guest pages population in a new flag (vhost_crypto/SPDK), - removed remaining helpers which had sync_ in their names, David Marchand (6): vhost: decouple guest pages population from async datapath examples/vhost: stop using async datapath examples/vdpa: remove dependency on PCI library vhost: drop async datapath vhost: rename packed layout helpers for batches vhost: simplify some descriptor handling doc/guides/prog_guide/vhost_lib.rst | 152 +- doc/guides/rel_notes/release_26_11.rst | 24 + doc/guides/sample_app_ug/vhost.rst | 10 - examples/vdpa/main.c | 1 - examples/vhost/Makefile | 2 - examples/vhost/main.c | 437 +--- examples/vhost/main.h | 21 +- examples/vhost/meson.build | 2 - examples/vhost_crypto/Makefile | 1 - examples/vhost_crypto/main.c | 2 +- examples/vhost_crypto/meson.build | 1 - lib/vhost/meson.build | 3 +- lib/vhost/rte_vhost.h | 2 +- lib/vhost/rte_vhost_async.h | 293 --- lib/vhost/socket.c | 18 +- lib/vhost/vhost.c | 436 ---- lib/vhost/vhost.h | 118 +- lib/vhost/vhost_user.c | 115 +- lib/vhost/virtio_net.c | 3317 +++++------------------- 19 files changed, 729 insertions(+), 4226 deletions(-) delete mode 100644 lib/vhost/rte_vhost_async.h -- 2.54.0