From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752274Ab2ASKhQ (ORCPT ); Thu, 19 Jan 2012 05:37:16 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:53716 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750988Ab2ASKhL (ORCPT ); Thu, 19 Jan 2012 05:37:11 -0500 Date: Thu, 19 Jan 2012 11:37:07 +0100 From: Pavel Machek To: Tejun Heo Cc: "Srivatsa S. Bhat" , "Rafael J. Wysocki" , Linux PM list , LKML , horms@verge.net.au, Len Brown Subject: Re: [Update][PATCH] PM / Hibernate: Fix s2disk regression related to unlock_system_sleep() Message-ID: <20120119103707.GA13308@elf.ucw.cz> References: <201201172345.15010.rjw@sisk.pl> <201201180015.56510.rjw@sisk.pl> <4F16C24A.4050007@linux.vnet.ibm.com> <4F16F94C.4020000@linux.vnet.ibm.com> <4F16FF0D.1030606@linux.vnet.ibm.com> <20120118173037.GE30664@google.com> <20120118173348.GF30664@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120118173348.GF30664@google.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! > > > I agree, but I was trying to keep the comment from growing too long ;) > > > > It doesn't have to be long. It just has to give some meaning to the > > decision. AFAICS, it is correct to call try_to_freeze() on > > unlock_system_sleep() regardless of 20sec window. There's no > > guarantee the unlocking task is gonna hit try_to_freeze() elsewhere > > and not calling it actually makes the interface buggy. > > To give an example, > > /* > * XXX: Open code SKIP clearing for now to avoid invoking > * try_to_freeze(). This isn't correct but this function is > * called from deep inside hibernation path and calling > * try_to_freeze() leads to hang during hibernation. This > * will be properly fixed soon. See commit message for > * more details. > */ Which paths are affected? With uswsusp, we have userland in control of hibernation process; I'd say almost anything can be called... Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html