From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: Linux 3.0-rc4 intermittent failure to resume Date: Wed, 29 Jun 2011 21:34:34 +0200 Message-ID: <201106292134.34485.rjw@sisk.pl> References: <4E0286F3.6030003@wasp.net.au> <4E093ECD.7040600@fnarfbargle.com> <4E0B2737.2010505@fnarfbargle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4E0B2737.2010505@fnarfbargle.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Brad Campbell Cc: linux-pm@lists.linux-foundation.org List-Id: linux-pm@vger.kernel.org On Wednesday, June 29, 2011, Brad Campbell wrote: > On 28/06/11 10:39, Brad Campbell wrote: > > On 24/06/11 10:41, Brad Campbell wrote: > >> On 23/06/11 20:02, Rafael J. Wysocki wrote: > >>> On Thursday, June 23, 2011, Brad Campbell wrote: > >>>> G'day all, > >>>> > >>>> I've recently moved from tuxonice to mainline uswsusp. I'm getting intermittent failure to resume > >>>> problems. No message in dmesg that I can find, it just boots clean. Is there something I can do to > >>>> get some debug info on this? It's really, really annoying. > >>>> > >>>> About 75% of the time it works perfectly, and I can find no rhyme or reason to why it suddenly just > >>>> decides to ignore the saved state. > >>>> > >>>> 32 bit userspace with a statically linked 64 bit s2disk, s2both& resume. 64 bit kernel. > >>> Do you use the i915 driver? > >>> > >> Indeed I do. > > Just a follow up to this. > > It looks like adding "early writeout = y" to my /etc/suspend.conf has worked around the problem. > > > > Ok, so after _lots_ of investigating it was not early writeout. The > culprit was/is the Ubuntu initramfs scripts. > > On the occasions it failed to resume (which were many) it turns out > /bin/resume was being called prior to udev having created /dev/snapshot. > > I put a simple wait loop in the resume script to wait for the creation > of /dev/snapshot and I've not had a fail to resume since. > > Curse you asynchronous dynamic device creation Thank you very much for nailing this down, I was afraid there were some obscure bug lurking in the kernel code. Take care, Rafael