From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992540AbXCGXG7 (ORCPT ); Wed, 7 Mar 2007 18:06:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992709AbXCGXG7 (ORCPT ); Wed, 7 Mar 2007 18:06:59 -0500 Received: from mx1.redhat.com ([66.187.233.31]:53489 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992540AbXCGXG6 (ORCPT ); Wed, 7 Mar 2007 18:06:58 -0500 Date: Wed, 7 Mar 2007 15:02:27 -0800 From: Pete Zaitcev To: Alan Stern Cc: ebuddington@wesleyan.edu, Oliver Neukum , USB development list , Kernel development list Subject: Re: [linux-usb-devel] khubd and ent:sda1 sucking CPU with reiser4 + USB HD Message-Id: <20070307150227.e5395d6c.zaitcev@redhat.com> In-Reply-To: References: <20070307204722.GA3605@pool-71-123-121-36.spfdma.east.verizon.net> Organization: Red Hat, Inc. X-Mailer: Sylpheed 2.3.1 (GTK+ 2.10.9; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 7 Mar 2007 17:18:29 -0500 (EST), Alan Stern wrote: > I've never heard of a process failing to show up in a SysRq-t listing. It > suggests something is wrong with the process management in the kernel you > were using. That leads me to think a non -mm kernel might give more > informative results. I think, if a process is looping, it's not shown in SysRq-t. So maybe khubd is on a CPU. In RHEL we have a patch for SysRq-w, which showed all CPU states by the way of a special IPI (unless looping with closed interrups, of course). But this capability seems a bit degraded in stock SysRq-w. It might not catch this (does not seem for me in 2.6.20). Another possibility is, something killed khubd. It's only a process after all. Remember how we had grief with it being killed by "telinit 1". -- Pete