From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755628Ab0JJSEM (ORCPT ); Sun, 10 Oct 2010 14:04:12 -0400 Received: from ksp.mff.cuni.cz ([195.113.26.206]:57196 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753513Ab0JJSEK (ORCPT ); Sun, 10 Oct 2010 14:04:10 -0400 Date: Sun, 10 Oct 2010 20:04:00 +0200 From: Pavel Machek To: James Hogan Cc: linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Len Brown , "Rafael J. Wysocki" , Randy Dunlap , Greg Kroah-Hartman , Alan Stern , Jesse Barnes , markgross Subject: Re: [PATCH 2/2] pm_trace: Add sysfs attr for rechecking dev hash. Message-ID: <20101010180400.GA19524@elf.ucw.cz> References: <201010092334.27808.james@albanarts.com> <201010092337.47821.james@albanarts.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201010092337.47821.james@albanarts.com> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! > If the device which fails to resume is part of a loadable kernel module > it won't be checked at startup against the magic number stored in the > RTC. > > Add a read-only sysfs attribute /sys/power/pm_trace_dev_hash which > contains a list of newline separated devices (usually just the one) > which currently match the last magic number. This allows the device > which is failing to resume to be found after the modules are loaded > again. > --- a/Documentation/power/s2ram.txt > +++ b/Documentation/power/s2ram.txt > @@ -49,6 +49,13 @@ machine that doesn't boot) is: > device (lspci and /sys/devices/pci* is your friend), and see if you can > fix it, disable it, or trace into its resume function. > > + If no device matches the hash, it may be a device from a loadable kernel > + module that is not loaded until after the hash is checked. You can check > + the hash against the current devices again after more modules are loaded > + using sysfs: > + > + cat /sys/power/pm_trace_dev_hash > + Yep, but exact semantics of that sysfs file should probably be linked in the sysfs documentation... Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html