Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 3 Nov 2002 19:36:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 3 Nov 2002 19:36:18 -0500 Received: from nat-pool-rdu.redhat.com ([66.187.233.200]:64920 "EHLO devserv.devel.redhat.com") by vger.kernel.org with ESMTP id ; Sun, 3 Nov 2002 19:36:17 -0500 Date: Sun, 3 Nov 2002 19:42:49 -0500 From: Pete Zaitcev To: William Lee Irwin III Cc: Pete Zaitcev , linux-kernel@vger.kernel.org Subject: Re: interrupt checks for spinlocks Message-ID: <20021103194249.A1603@devserv.devel.redhat.com> References: <200211040028.gA40S8600593@devserv.devel.redhat.com> <20021104002813.GZ16347@holomorphy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20021104002813.GZ16347@holomorphy.com>; from wli@holomorphy.com on Sun, Nov 03, 2002 at 04:28:13PM -0800 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 818 Lines: 22 > Date: Sun, 3 Nov 2002 16:28:13 -0800 > From: William Lee Irwin III > >> (1) check that spinlocks are not taken in interrupt context without > >> interrupts disabled > > Bill, why is this bad? I routinely use this technique. > > -- Pete > > If you receive the same interrupt on the same cpu and re-enter code > that does that, you will deadlock. How would that happen? I thought it was not possible to re-enter an interrupt, and that it was pretty fundamental for Linux. When did we allow it, and what are implications for architectures? -- Pete - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/