From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Walker Subject: Re: [PATCH -rt DO NOT APPLY] Fix for tg3 networking lockup Date: Thu, 03 Aug 2006 17:03:05 -0700 Message-ID: <1154649785.16126.3.camel@dwalker1.mvista.com> References: <20060803201741.GA7894@thunk.org> <20060803.144845.66061203.davem@davemloft.net> <20060803235326.GC7894@thunk.org> <20060803.165654.45876296.davem@davemloft.net> Reply-To: dwalker@mvista.com Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: tytso@mit.edu, mchan@broadcom.com, herbert@gondor.apana.org.au, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Return-path: Received: from gateway-1237.mvista.com ([63.81.120.158]:11382 "EHLO gateway-1237.mvista.com") by vger.kernel.org with ESMTP id S1030238AbWHDADH (ORCPT ); Thu, 3 Aug 2006 20:03:07 -0400 To: David Miller In-Reply-To: <20060803.165654.45876296.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Thu, 2006-08-03 at 16:56 -0700, David Miller wrote: > From: Theodore Tso > Date: Thu, 3 Aug 2006 19:53:26 -0400 > > > Any suggestions on how I could figure out what was really going on and > > what would be a better fix would be greatly appreciated. > > As Michael explained, it's the ASF heartbeat sent by tg3_timer() that > must be delivered to the chip within certain timing constraints. > > If you had any watchdog devices on this machine, they would likely > trigger too and reset your machine :) That's not broken behavior in RT .. That's just plain old task priorities. Some high priority task (SCHED_FIFO prio 99) is sucking up a lot of the CPU. But that's 100% legal in SCHED_FIFO. Daniel