From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261357AbVGTPD7 (ORCPT ); Wed, 20 Jul 2005 11:03:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261323AbVGTPD7 (ORCPT ); Wed, 20 Jul 2005 11:03:59 -0400 Received: from dgate1.fujitsu-siemens.com ([217.115.66.35]:4528 "EHLO dgate1.fujitsu-siemens.com") by vger.kernel.org with ESMTP id S261357AbVGTPCo (ORCPT ); Wed, 20 Jul 2005 11:02:44 -0400 X-SBRSScore: None X-IronPort-AV: i="3.93,304,1114984800"; d="scan'208"; a="12868361:sNHT31551564" Message-ID: <42DE6791.2030305@fujitsu-siemens.com> Date: Wed, 20 Jul 2005 17:02:41 +0200 From: Martin Wilck Organization: Fujitsu Siemens Computers User-Agent: Mozilla Thunderbird 0.5 (X11/20040208) X-Accept-Language: de, en-us, en MIME-Version: 1.0 To: Alexander Nyberg Cc: linux-kernel@vger.kernel.org Subject: Re: files_lock deadlock? References: <42DD2E37.3080204@fujitsu-siemens.com> <1121870871.1103.14.camel@localhost.localdomain> In-Reply-To: <1121870871.1103.14.camel@localhost.localdomain> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Alexander Nyberg wrote: > spin_lock_irqsave is only needed when a lock is taken both in normal > context and in interrupt context. Clearly this lock is not intended to > be taken in interrupt context. According to Rusty's unreliable guide (http://www.kernel.org/pub/linux/kernel/people/rusty/kernel-locking/c214.html) if some code can be called from user context as well as in a softirq, at least spin_lock_bh() is necessary. I am not sure whether that may be true for the code that modifies files_lock. > I'll take a look, that spinlock debugging information unfortunately > doesn't give too much info :| Thanks! Martin -- Martin Wilck Phone: +49 5251 8 15113 Fujitsu Siemens Computers Fax: +49 5251 8 20409 Heinz-Nixdorf-Ring 1 mailto:Martin.Wilck@Fujitsu-Siemens.com D-33106 Paderborn http://www.fujitsu-siemens.com/primergy