From owner-freebsd-stable@FreeBSD.ORG Mon Jan 24 01:25:53 2005 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6BE2B16A4CE; Mon, 24 Jan 2005 01:25:53 +0000 (GMT) Received: from smtp2.server.rpi.edu (smtp2.server.rpi.edu [128.113.2.2]) by mx1.FreeBSD.org (Postfix) with ESMTP id 4B47A43D31; Mon, 24 Jan 2005 01:25:49 +0000 (GMT) (envelope-from drosih@rpi.edu) Received: from [128.113.24.47] (gilead.netel.rpi.edu [128.113.24.47]) by smtp2.server.rpi.edu (8.13.0/8.13.0) with ESMTP id j0O1Pkgl022743; Sun, 23 Jan 2005 20:25:47 -0500 Mime-Version: 1.0 Message-Id: In-Reply-To: References: Date: Sun, 23 Jan 2005 20:25:45 -0500 To: Robert Watson , stable@freebsd.org From: Garance A Drosihn Content-Type: text/plain; charset="us-ascii" ; format="flowed" X-CanItPRO-Stream: default X-RPI-SA-Score: undef - spam-scanning disabled X-Scanned-By: CanIt (www . canit . ca) cc: imp@freebsd.org Subject: Re: NULL pointer deref in sioopen() suggests a close/open race on sio device? X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 24 Jan 2005 01:25:54 -0000 At 4:51 PM +0000 1/23/05, Robert Watson wrote: > >The ps list is a bit boring, but the primary interesting thing is >that it looks like the close was going on in one thread just about >when the sio swi was scheduled to run also: [...] > This in turn suggests that something has called ttyrel/tty_close >on the TTY in a race with the open, or otherwise NULL'd that pointer >via knlist_destroy(). Anyone have any pointers on this one? The >TTY code is not my forte... FWIW, I just recently setup some of my freebsd boxes with serial consoles. It *seems* to me that if I type in 'shutdown -r now' when I am logged into a serial console, there's often some long delay before the reboot happens. It's long enough to be annoying, but not long enough to motivate me to look into it. My machines usually have a monitor/keyboard also setup on them, so my solution has been to avoid using the serial console... -- Garance Alistair Drosehn = gad@gilead.netel.rpi.edu Senior Systems Programmer or gad@freebsd.org Rensselaer Polytechnic Institute or drosih@rpi.edu