From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932292AbWHQF2g (ORCPT ); Thu, 17 Aug 2006 01:28:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751302AbWHQF2f (ORCPT ); Thu, 17 Aug 2006 01:28:35 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:17334 "EHLO ogre.sisk.pl") by vger.kernel.org with ESMTP id S1750972AbWHQF2f (ORCPT ); Thu, 17 Aug 2006 01:28:35 -0400 From: "Rafael J. Wysocki" To: Andrew Morton Subject: Re: [PATCH 3/3] PM: Remove PM_TRACE from Kconfig Date: Thu, 17 Aug 2006 07:32:39 +0200 User-Agent: KMail/1.9.3 Cc: LKML , Pavel Machek References: <200608162259.00941.rjw@sisk.pl> <200608162305.34038.rjw@sisk.pl> <20060816145242.32faa669.akpm@osdl.org> In-Reply-To: <20060816145242.32faa669.akpm@osdl.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200608170732.40048.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 16 August 2006 23:52, Andrew Morton wrote: > On Wed, 16 Aug 2006 23:05:33 +0200 > "Rafael J. Wysocki" wrote: > > > Remove the CONFIG_PM_TRACE option, which is dangerous and should only be used > > by people who know exactly what they are doing, from kernel/power/Kconfig . > > > > Signed-off-by: Rafael J. Wysocki > > Acked-by: Pavel Machek > > --- > > kernel/power/Kconfig | 18 ------------------ > > 1 files changed, 18 deletions(-) > > > > Index: linux-2.6.18-rc4-mm1/kernel/power/Kconfig > > =================================================================== > > --- linux-2.6.18-rc4-mm1.orig/kernel/power/Kconfig > > +++ linux-2.6.18-rc4-mm1/kernel/power/Kconfig > > @@ -47,24 +47,6 @@ config PM_DISABLE_CONSOLE_SUSPEND > > suspend/resume routines, but may itself lead to problems, for example > > if netconsole is used. > > > > -config PM_TRACE > > - bool "Suspend/resume event tracing" > > - depends on PM && PM_DEBUG && X86_32 && EXPERIMENTAL > > - default n > > - ---help--- > > - This enables some cheesy code to save the last PM event point in the > > - RTC across reboots, so that you can debug a machine that just hangs > > - during suspend (or more commonly, during resume). > > - > > - To use this debugging feature you should attempt to suspend the machine, > > - then reboot it, then run > > - > > - dmesg -s 1000000 | grep 'hash matches' > > - > > - CAUTION: this option will cause your machine's real-time clock to be > > - set to an invalid time after a resume. > > - > > - > > config SOFTWARE_SUSPEND > > bool "Software Suspend" > > depends on PM && SWAP && (X86 && (!SMP || SUSPEND_SMP)) || ((FRV || PPC32) && !SMP) > > So... how are people supposed to turn it on again? By patching the > kernel? That's a bit painful if they're using (say) fedora-of-the-day. > > How about we add a kernel boot parameter to enable it at runtime? I'm considering a sysfs attribute in /sys/power . If PM_TRACE is compiled in, an attribute, say "pm_trace", shows up in sysfs which is initially set to 0 and the user has to explicitly set it to 1 to enable the feature? Pavel, what do you think? Rafael -- You never change things by fighting the existing reality. R. Buckminster Fuller