From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S269203AbUHZRNH (ORCPT ); Thu, 26 Aug 2004 13:13:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S269241AbUHZRNF (ORCPT ); Thu, 26 Aug 2004 13:13:05 -0400 Received: from e33.co.us.ibm.com ([32.97.110.131]:39818 "EHLO e33.co.us.ibm.com") by vger.kernel.org with ESMTP id S269203AbUHZRMR (ORCPT ); Thu, 26 Aug 2004 13:12:17 -0400 Subject: kstopmachine thread panic in do_exit (2.6.9-rc1-bk1) From: Nathan Lynch To: Linus Torvalds Cc: lkml , Ingo Molnar , Rusty Russell Content-Type: text/plain Message-Id: <1093540274.4249.48.camel@biclops.private.network> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Thu, 26 Aug 2004 12:11:14 -0500 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi- Something crept in between 2.6.9-rc1 and 2.6.9-rc1-bk1 which reliably trips the "Aiee, killing interrupt handler!" panic in do_exit when offlining a cpu. I inserted a BUG() before the panic call to see what's causing it, looks like one of the kstopmachine threads spawned by stop_machine. I can't do a comparison with current -mm because offlining a cpu doesn't even get that far there. Backing out the most recent sched.c change ("sched: smt fixes" as of this writing) fixes it. Turning off preempt seems to work around it. The bug is still present in -bk2. I'm seeing this on a 4-way ppc64 machine. Nathan