Re: Thinkpad suspend-to-disk regression

Guilherme Salgado
2007-05-02T17:28:21Z

On 4/25/07, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> On Wednesday, 25 April 2007 04:25, Guilherme Salgado wrote:
> > On 4/24/07, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> > > On Tuesday, 24 April 2007 20:29, Guilherme Salgado wrote:
> > > > (I've already sent this to linux-acpi but got no response so far, so I
> > > > thought it could be a good idea to send directly to you)
> > > >
> > > > Hi there,
> > > >
> > > > I recently noticed that my thinkpad T60 would lose the sound after
> > > > being suspended to disk (https://launchpad.net/bugs/80893), requiring
> > > > a cold restart to fix it. After some git-bisect work I found this
> > > > regression was a consequence of
> > > > http://git.kernel.org/?p=linux/kernel/git/lenb/linux-acpi-2.6.git;a=commitdiff;h=9185cfa92507d07ac787bc73d06c42222eec7239
> > > > (patch inlined here)
> > > >
> > > > Is there any chance of fixing the regression this introduced without
> > > > reverting it? Please let me know if you want any other info or have a
> > > > patch for me to try.
> > >
> > > You don't need a patch, I think. Please try
> > >
> > > # echo shutdown > /sys/power/disk
> > >
> > > before the suspend (assuming you use the built-in swsusp). If that works,
> > > just make your configuration scripts echo 'shutdown' to /sys/power/disk at
> > > system startup.
> > >
> >
> > I use Ubuntu's default /etc/acpi/hibernate.sh, which already sets
> > /sys/power/disk to shutdown before echoing "disk" to /sys/power/state.
>
> In that case it's impossible that the commit you have identified causes the
> problem to happen.
>
> It doesn't even touch the 'shutdown' code path.

Is it be possible that the change to /sys/power/disk is not doing what
it should? I think that's likely to be the case because I got a bunch
of people to try a kernel with the patch reverted and it fixed the
problem they were having.

The most recent comments at https://bugs.launchpad.net/+bugs/80893 are
all confirming that the kernel at
http://rookery.ubuntu.com/~kyle/kernels/salgado/2007-04-25/ fixes
their problem.

I'd be glad to do anything to further debug this if you can give me
some pointers.

Cheers,
Guilherme