From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Subject: Re: [Bugme-new] [Bug 10737] New: pktgen procfs problem Date: Sun, 18 May 2008 15:24:25 +0200 Message-ID: <48302E09.8080701@trash.net> References: <20080517141036.d8f3c768.akpm@linux-foundation.org> <482F88DE.8090508@trash.net> <20080517215641.acb94677.akpm@linux-foundation.org> <48301BE0.9040907@trash.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, bugme-daemon@bugzilla.kernel.org, devzero@web.de, Robert Olsson , "Denis V. Lunev" To: Andrew Morton Return-path: Received: from stinky.trash.net ([213.144.137.162]:36876 "EHLO stinky.trash.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752996AbYERNY1 (ORCPT ); Sun, 18 May 2008 09:24:27 -0400 In-Reply-To: <48301BE0.9040907@trash.net> Sender: netdev-owner@vger.kernel.org List-ID: Patrick McHardy wrote: > Andrew Morton wrote: >> On Sun, 18 May 2008 03:39:42 +0200 Patrick McHardy >> wrote: >> >> >>> I've been looking into the same problem, without much success so >>> far. The problem appears to affect any /proc/net file, but not >>> files outside of /proc/net, so I'm guessing its net-ns related. >>> A testcase found by Ben Greear is opening the file multiple times: >>> >>> # /tmp/open /proc/net/kpktgen_0 >>> >>> => refcnt goes to 1 >>> >>> ^C >>> >>> => refcnt goes to 0 >>> >>> Without ^C and opening the file a second time: >>> >>> # /tmp/open /proc/net/kpktgen_0 >>> >>> => refcnt goes to 2 (sometimes also 11) >>> >>> ^C >>> >>> => refcnt stays at previous value. >>> >>> The refcnt even leaks if the file can't be successfully opened, >>> for example because of lacking permissions. >>> >> >> urgh. Is any of this known to be post-2.6.25? >> > > 2.6.25 is also affected. I don't know about earlier kernels. Some more information: the problem seems to occur only if the file is opened by two different processes. I'm starting a bisection now.