From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 29BB6A052B; Tue, 28 Jul 2020 03:34:21 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 0A3341BFF3; Tue, 28 Jul 2020 03:34:21 +0200 (CEST) Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by dpdk.org (Postfix) with ESMTP id F40902B8D for ; Tue, 28 Jul 2020 03:34:18 +0200 (CEST) IronPort-SDR: BqRgICm5cIzCUXX0ZrX1pN7K7cbHwu3NTqJV90Rt34C7HrIl3Gsu7HFkrIklgc4dTyZVlbTvA9 VFKMlg23BNbA== X-IronPort-AV: E=McAfee;i="6000,8403,9695"; a="215666741" X-IronPort-AV: E=Sophos;i="5.75,404,1589266800"; d="scan'208";a="215666741" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Jul 2020 18:34:17 -0700 IronPort-SDR: nT0CYYdfLgIc8KOyvSdpwxdtyLrCIFxRJDM1J92TXMmi/urKw6XLwOLjW2hfuP4nmTapiyXgB2 SSkwLuaa7Sdg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,404,1589266800"; d="scan'208";a="312424888" Received: from dpdk-xuanding-dev2.sh.intel.com ([10.67.119.173]) by fmsmga004.fm.intel.com with ESMTP; 27 Jul 2020 18:34:16 -0700 From: Xuan Ding To: maxime.coquelin@redhat.com, zhihong.wang@intel.com, Chenbo.Xia@intel.com Cc: dev@dpdk.org, Xuan Ding Date: Tue, 28 Jul 2020 01:33:47 +0000 Message-Id: <20200728013347.40746-1-xuan.ding@intel.com> X-Mailer: git-send-email 2.17.1 Subject: [dpdk-dev] [PATCH] doc: vhost multi-queue reconnection known issue X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" This patch added known issue for vhost multi-queue reconnection with virtio-net/virtio-pmd. Signed-off-by: Xuan Ding --- doc/guides/rel_notes/known_issues.rst | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/doc/guides/rel_notes/known_issues.rst b/doc/guides/rel_notes/known_issues.rst index de0782136..3359cf063 100644 --- a/doc/guides/rel_notes/known_issues.rst +++ b/doc/guides/rel_notes/known_issues.rst @@ -888,3 +888,24 @@ Unsuitable IOVA mode may be picked as the default **Driver/Module**: ALL. + +Vhost multi-queue reconnection failed with QEMU version >= 4.2.0 +------------------------------------------------- + +**Description** + It's a QEMU regression bug (bad commit: c6beefd674ff). QEMU only saves + acked features for one vhost-net when vhost quits. When vhost reconnects + to virtio-net/virtio-pmd in multi-queue situations, the features been + set multiple times are not consistent. + +**Implication** + Vhost cannot reconnect back to virtio-net/virtio-pmd normally. + +**Resolution/Workaround**: + It is possible to filter the incorrect acked features at vhost-user side. + +**Affected Environment/Platform**: + ALL. + +**Driver/Module**: + Virtual Device Poll Mode Driver (PMD). -- 2.17.1