Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756635AbYGaSBX (ORCPT ); Thu, 31 Jul 2008 14:01:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752339AbYGaSBP (ORCPT ); Thu, 31 Jul 2008 14:01:15 -0400 Received: from rv-out-0506.google.com ([209.85.198.228]:47290 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751587AbYGaSBN (ORCPT ); Thu, 31 Jul 2008 14:01:13 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=vDG5Bw8BQDG3ycVBBR4Xl8qn9Q0AODfEL9jTarXrDtKa/XDh0NiK86r565/iJFDRwh yyKqdyukrZTDS/2bbQIfx24Wzl6mdA6/fIzaFmeBlwhymmnyjm6vBZ+S8YY8iuv+6MWs 7Sgr0mJLUJZY8pPsMOcqVVJTwnkXhfeUkuG+4= Message-ID: Date: Thu, 31 Jul 2008 20:01:12 +0200 From: "Zdenek Kabelac" To: "Henrique de Moraes Holschuh" Subject: Re: Sysrq+B doesn't work on my box Cc: "Linux Kernel Mailing List" In-Reply-To: <20080731143905.GF19665@khazad-dum.debian.net> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080731143905.GF19665@khazad-dum.debian.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2139 Lines: 47 2008/7/31 Henrique de Moraes Holschuh : > On Thu, 31 Jul 2008, Zdenek Kabelac wrote: >> I'd like to get resolved this problem - my T61 machine doesn't reboot >> with SysRQ+B key. >> And I never remember if it was ever rebooting. >> >> This is all I know so far and I've no idea where could be the problem. > > Well, many of the different ThinkPad BIOSes are really sensitive to the > proper boot/reboot/shutdown sequence (whatever it is). Otherwise, the thing > gets stuck in SMBIOS limbo and hung. For exeample, we had major issues with > boxes that only shut down half-way and ended up draining the cells to > critical levels, a few months ago. I don't know what finally fixed THAT > one, but it was ugly. > > Here is another example: you can't get the TCO watchdog to reboot all (any?) > thinkpads properly on hardware. In my T43, the TCO watchdog IS hooked to > something, but the BIOS hates it to trip and the entire box goes to > neverland when it fires... > > If sysrq+b uses a different reboot path than the normal reboot path, it is > the first hint of what is missing... I've spend some time with tracking this issue more - and I've discovered this: SysRQ+B doesn't work with right AltGr on my keyboard - but it does work with the left Alt which I'm not normally using (It's somewhat easier to use the right one) Any idea why AltGR+SysRQ+b does not work on T61 ? Blocking reboot goes through the arch/x86/kernel/reboot.c native_machine_emergency_restart() case BOOT_KBD: (10 loop outb() iteration) and ends in case BOOT_TRIPLE: int3 - there it stays forever - during the press of poweroff button it even visits that sysrq __handler. if the kernel is started with init=/bin/sh - boot works without problems - so it looks like that disabling reboot capability is the result of Fedora's rc.sysinit process. Yet I've no idea what that could be.... Zdenek -- 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/