From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965820AbXCIUnV (ORCPT ); Fri, 9 Mar 2007 15:43:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965818AbXCIUnV (ORCPT ); Fri, 9 Mar 2007 15:43:21 -0500 Received: from electric-eye.fr.zoreil.com ([213.41.134.224]:59485 "EHLO fr.zoreil.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965817AbXCIUnU (ORCPT ); Fri, 9 Mar 2007 15:43:20 -0500 Date: Fri, 9 Mar 2007 21:42:43 +0100 From: Francois Romieu To: Simon Arlott Cc: Linux Kernel Mailing List , netdev@vger.kernel.org Subject: Re: netconsole system freeze when cable unplugged Message-ID: <20070309204243.GA28441@electric-eye.fr.zoreil.com> References: <45F1B6FD.1060902@simon.arlott.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <45F1B6FD.1060902@simon.arlott.org.uk> User-Agent: Mutt/1.4.2.1i X-Organisation: Land of Sunshine Inc. Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Simon Arlott : > When I unplug the cable the system just stops responding to anything, > at all. No message is printed to the console when the cable is plugged > back in. rtl8139_interrupt (spin_lock(&tp->lock)) -> rtl8139_weird_interrupt -> rtl_check_media -> mii_check_media (printk(KERN_INFO "%s: link down\n", ...)) [netpoll stuff here] -> rtl8139_poll_controller -> rtl8139_interrupt *deadlock* See below for my random stuff of the day. Feel free to open a PR at bugzilla.kernel.org if the issue does not go away. --------8<----------------------------------------------------------------- 8139too: netconsole breakage when link changes rtl8139_interrupt is not supposed to be reentrant but its link management part can emit printk. Signed-off-by: Francois Romieu diff --git a/drivers/net/8139too.c b/drivers/net/8139too.c index 99304b2..64467ad 100644 --- a/drivers/net/8139too.c +++ b/drivers/net/8139too.c @@ -2215,9 +2215,16 @@ static irqreturn_t rtl8139_interrupt (int irq, void *dev_instance) */ static void rtl8139_poll_controller(struct net_device *dev) { - disable_irq(dev->irq); + struct rtl8139_private *tp = netdev_priv(dev); + unsigned long flags; + int rc; + + rc = spin_trylock_irqsave(&tp->lock, flags); + if (!rc) + return; + spin_unlock(&tp->lock); rtl8139_interrupt(dev->irq, dev); - enable_irq(dev->irq); + local_irq_restore(flags); } #endif