From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47120) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cMwVA-0005vN-4K for qemu-devel@nongnu.org; Fri, 30 Dec 2016 07:41:40 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cMwV7-00058q-2c for qemu-devel@nongnu.org; Fri, 30 Dec 2016 07:41:40 -0500 Received: from mail-qk0-f181.google.com ([209.85.220.181]:34963) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cMwV6-00058Z-VX for qemu-devel@nongnu.org; Fri, 30 Dec 2016 07:41:37 -0500 Received: by mail-qk0-f181.google.com with SMTP id u25so285479273qki.2 for ; Fri, 30 Dec 2016 04:41:36 -0800 (PST) Date: Fri, 30 Dec 2016 10:41:30 -0200 From: Flavio Leitner Message-ID: <20161230104130.29ff671b@x240.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] vhost-user breaks after 96a3d98. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jason Wang , "Michael S. Tsirkin" Cc: qemu-devel Hi, While I was testing vhost-user using OVS 2.5 and DPDK 2.2.0 in the host and testpmd dpdk 2.2.0 in the guest, I found that the commit below breaks the environment and no packets gets into the guest. dpdk port --> OVS --> vhost-user --> guest --> testpmd ^--- drops here ^--- no packets here. commit 96a3d98d2cdbd897ff5ab33427aa4cfb94077665 Author: Jason Wang Date: Mon Aug 1 16:07:58 2016 +0800 vhost: don't set vring call if no vector We used to set vring call fd unconditionally even if guest driver does not use MSIX for this vritqueue at all. This will cause lots of unnecessary userspace access and other checks for drivers does not use interrupt at all (e.g virtio-net pmd). So check and clean vring call fd if guest does not use any vector for this virtqueue at all. [...] Thanks, -- Flavio