From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751423AbVIINiJ (ORCPT ); Fri, 9 Sep 2005 09:38:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751428AbVIINiJ (ORCPT ); Fri, 9 Sep 2005 09:38:09 -0400 Received: from relay7.mail.ox.ac.uk ([129.67.1.167]:10928 "EHLO relay7.mail.ox.ac.uk") by vger.kernel.org with ESMTP id S1751423AbVIINiH (ORCPT ); Fri, 9 Sep 2005 09:38:07 -0400 Date: Fri, 9 Sep 2005 14:38:04 +0100 From: Ian Collier To: linux-kernel@vger.kernel.org Subject: Re: 2.6.13: loop ioctl crashes Message-ID: <20050909143804.A23692@pixie.comlab> Mail-Followup-To: linux-kernel@vger.kernel.org References: <20050909132725.C23462@pixie.comlab> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: ; from linux-os@analogic.com on Fri, Sep 09, 2005 at 08:32:10AM -0400 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 09, 2005 at 08:32:10AM -0400, linux-os (Dick Johnson) wrote: > I guess you are trying to do a copy_from_user() with a spin-lock > being held or the interrupts otherwise disabled. You can hold > a semaphore, to prevent somebody else from interfering with > you, but you cannot hold a spin-lock during copy/to/from/user(). Well, I didn't write the code (it's right there in drivers/block/loop.c in 2.6.13) and I can't see where there's a spin-lock. In fact it does use a semaphore. imc