From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [PATCH] iproute: Properly handle protocol level diag module absence Date: Mon, 10 Feb 2014 14:37:31 -0800 Message-ID: <20140210143731.34b73a78@nehalam.linuxnetplumber.net> References: <52E7E990.7050501@parallels.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Stephen Hemminger , Linux Netdev List , =?ISO-8859-1?B?RnJhbudvaXMtWGF2aWVy?= Le Bail To: Pavel Emelyanov Return-path: Received: from mail-pa0-f45.google.com ([209.85.220.45]:47987 "EHLO mail-pa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752260AbaBJWhf convert rfc822-to-8bit (ORCPT ); Mon, 10 Feb 2014 17:37:35 -0500 Received: by mail-pa0-f45.google.com with SMTP id lf10so6772370pab.18 for ; Mon, 10 Feb 2014 14:37:34 -0800 (PST) In-Reply-To: <52E7E990.7050501@parallels.com> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 28 Jan 2014 21:32:00 +0400 Pavel Emelyanov wrote: > When *_diag module is missing in the kernel, the ss tool should go > ad read legacry /proc/* files. >=20 > This is the case when all *_diag stuff is missing, but in case the > inet_diag.ko is loaded, but (tcp|udp)_diag.ko is not, the ss tool > doesn't notice this and produces empty output. The reason for that > is -- error from the inet_diag module (which means, that e.g. the > udp_diag is missing) is reported in the NLMSG_DONE message body. >=20 > That said, we need to check the NLMSG_DONE's message return code > and act respectively. >=20 > Reported-by: Fran=E7ois-Xavier Le Bail > Signed-off-by: Pavel Emelyanov >=20 Silently ignoring the error seems wrong. The fallback is good, but we should try and report the error so that the user fixes the kernel config.