From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <stephen@networkplumber.org>
Received: from mail-pf1-f196.google.com (mail-pf1-f196.google.com
 [209.85.210.196]) by dpdk.org (Postfix) with ESMTP id 4B0941B1F3
 for <dev@dpdk.org>; Tue, 23 Oct 2018 17:57:02 +0200 (CEST)
Received: by mail-pf1-f196.google.com with SMTP id u12-v6so879007pfn.12
 for <dev@dpdk.org>; Tue, 23 Oct 2018 08:57:02 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=networkplumber-org.20150623.gappssmtp.com; s=20150623;
 h=date:from:to:cc:subject:message-id:mime-version
 :content-transfer-encoding;
 bh=BzhUU9ROU9Sn4wzU4okchXySHOLSfMXhRGbFJNwhYgk=;
 b=pDANK94/eKZhPl+gEZePWIv5+fvwCTMQCYnNwYW1/N4kvNg8szGAdiuK84jtABKI+B
 u4pJP75lqyW6wATFzQl4N0g5TBB0BGWRdKZPT85Qs6Wpqz+tYMwhfo3HiFBXFCWOM30N
 AJIjoul9U3bVlPbTQQPPdDf/+sWy6gNAi65bd/sg8T1D4GPD597x83KJtogn6vO1FwWe
 AE/mKjeRtVCX9UAAxK7cG0fdXx5tjRd+MjaagB14cDHHvVHXEdo2De/EFS69RcV+mfdV
 LIaaHRKTKw/oeuxgxblFIkW6i015WZBaFjb+mbtOaEq5oV73y2JqfpVPbtD1HqIHDimZ
 3GwA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=1e100.net; s=20161025;
 h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version
 :content-transfer-encoding;
 bh=BzhUU9ROU9Sn4wzU4okchXySHOLSfMXhRGbFJNwhYgk=;
 b=qIg0R+WnDYCBsJ8JzUNeZbGpBcAg03mPSfA+Eez9uGUaluyJOwNHI/GcIwjV+P1q69
 KvSR3XIu0D6l7ur5uxW91SVZlHSM1q5BtzSsl8bG5ZS90Zxdo3kdk9au3qzrkDlx0jmp
 2g7acpFOh2eMRod8P0RSS8JATsty5Pr4vHHoHNjXtKlfe5riW6thPGoXxJN7hHZhozWK
 sgku2cBy6XtJMXGizR5rkhuAC2c0ll2t4rCELCgZMwqHWJ9FQ4js3y0SKknmYKcKDGQT
 kaN1SXK7/lBMB1eJZdRrjz6KVQ/5nAF9uxMhTyNtMIL6P+yQ3WwOXi5T4TO/KiYzP8KF
 Ez/w==
X-Gm-Message-State: ABuFfohCRpro0lHEs7sJjRN679LBLYfY2dV5VvMyIr6HZuRybXoXzHj9
 XfvuJRn+6485JZtGzW+XyYMveQ==
X-Google-Smtp-Source: ACcGV63BzIeH6UUiDXnMlO/BSx8rjQXyX/J6aNbDYh+Yygnp/zKUFh1wqT/czmoLQiq9xhvlb2XVKA==
X-Received: by 2002:a63:40c2:: with SMTP id
 n185-v6mr47949302pga.116.1540310221263; 
 Tue, 23 Oct 2018 08:57:01 -0700 (PDT)
Received: from xeon-e3 (204-195-22-127.wavecable.com. [204.195.22.127])
 by smtp.gmail.com with ESMTPSA id v185-v6sm2095236pfv.48.2018.10.23.08.57.00
 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256);
 Tue, 23 Oct 2018 08:57:01 -0700 (PDT)
Date: Tue, 23 Oct 2018 08:56:58 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: Maxime Coquelin <maxime.coquelin@redhat.com>, Tiwei Bie
 <tiwei.bie@intel.com>
Cc: dev@dpdk.org
Message-ID: <20181023085658.10aa5301@xeon-e3>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Subject: [dpdk-dev] errors from VHOST on shutdown.
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://mails.dpdk.org/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://mails.dpdk.org/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <https://mails.dpdk.org/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
X-List-Received-Date: Tue, 23 Oct 2018 15:57:02 -0000

I get errors on shutdown of application using virtio-user.
For example, quitting testpmd:

Detaching a port...
vhost_kernel_set_backend(): VHOST_NET_SET_BACKEND fails, Operation not permitted
vhost_kernel_set_backend(): VHOST_NET_SET_BACKEND fails, Operation not permitted
vhost_kernel_ioctl(): VHOST_RESET_OWNER failed: Operation not permitted

Everything works fine, but not good to have this kind of thing visible to user.
These error messages should be fixed, or the error message removed.

How do you want to handle it?