Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 18 Mar 2002 11:43:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 18 Mar 2002 11:43:24 -0500 Received: from air-2.osdl.org ([65.201.151.6]:34823 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id ; Mon, 18 Mar 2002 11:43:14 -0500 Date: Mon, 18 Mar 2002 08:42:53 -0800 (PST) From: "Randy.Dunlap" X-X-Sender: To: Joachim Breuer cc: Subject: Re: 2.4.18 freezes on heavy IO; SysRq question In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 18 Mar 2002, Joachim Breuer wrote: | Richard Ems writes: | | > Hi all! | > | > I'm seeing my system freeze on heavy IO. Only the reset button brings it | > back to life again (ALT-SysRq-b also worked once). I'm running SuSE's | > 2.4.18-30 on a Pentium III (Coppermine) with 256 MB RAM (yes, I should | > try vanilla 2.4.18, I will ...) | > No SCSI, all IDE. LVM and ext3. | > I don't get any oopses, no entries in /var/log/messages, nothing. I | > mounted the ext3 partitions with the debug option but still no messages. | > What options can I turn on to search for the problem? Any kernel boot | > options? LVM/ext3 options? | | Seconded; happened to me with 2.4.18 from kernel.org + LVM 2.0 beta | 1.1 + Trond's NFS ('current' for 2.4.18). IO was to a local ext3 fs; | no LVM on that machine (modules not loaded). | | Lock-up was complete for me; no panic message and no IP either so I | couldn't poke around. Alt+Sysrq seemed dead; but it might have been on | one of the boxen where Linux does not detect Alt+Sysrq properly. | | BTW, what's the status of the Sysrq entry key "decoder"? I've about 4 | different types of keyboards here, as far as I could determine only | one of them sends Linux-parseable Alt-Sysrq. All do send *something* | on Alt-Sysrq, though; but I couldn't get them to work with the | procedure described in the SysRq manual. That was around 2.4.12. I've seen a couple of cheapo keyboards where some Alt-SysRq-key combinations don't generate anything from the keyboard. (I'm typing on one of them right now.) For example, Alt-SysRq-5|6 works, but 1,2,3,4,7,8,9 don't. I've been told that it's just keyboard manufacturers trying to save 1/2 cent each keyboard e.g. :( In any case, I have 2 patches that you might find useful. One patch uses Alt-SysRq-Y to raise the console loglevel by 1 and Alt-SysRq-V to lower it by 1. http://www.osdl.org/archive/rddunlap/patches/sysrq-logupdown.dif The other patch implements magic sysrq keys via sysctl. E.g., "echo 9 > /proc/sys/kernel/magickey" sets console loglevel to 9, and "echo m > /proc/sys/kernel/magickey" calls show_mem(). http://www.osdl.org/archive/rddunlap/patches/sys-magic.dif magickey updates go directly to the sysrq keyboard handler, so all current keycodes are supported. -- ~Randy - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/