Re: Linux 3.0-rc4 intermittent failure to resume

[Brad Campbell <lists2009@fnarfbargle.com>]

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 <shakes fist>

Regards,
Brad