Re: HDD not suspending properly / dead on resume

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Saturday, July 10, 2010, Stephan Diestelhorst wrote:
> Rafael J. Wysocki wrote:
> > On Friday, July 09, 2010, Stephan Diestelhorst wrote:
> > > I wrote:
> > > >   I have an issue with suspend to RAM and I/O load on a disk. Symptoms
> > > > are that the disk does not respond to requests when woken up, producing
> > > > only I/O errors on all tested kernels (newest 2.6.35-rc4 (Ubuntu
> > > > mainline PPA build)):
> > > > 
> > > <snip>
> > >  
> > > > This can be triggered most reliably with multiple "direct" writes to
> > > > disk, I create the load with the attached script. If the issue is
> > > > triggered, suspend (through pm-suspend) takes very long.
> > > 
> > > > IMHO the interesting log output during suspend is:
> > > > [ 1674.700125] ata1.00: qc timeout (cmd 0xec)
> > > 
> > > Almighty google suggested to try "pci=nomsi", which seems to have
> > > cured the issue for me for now. Is that plausible? I'll keep this
> > > under observation.
> > 
> > Hmm.  How does your /proc/interrupts look like?
> 
> This has been yet another red herring. After trying out the kernel
> option three times with two different kernels, it failed yet again
> with the same symptoms. 

I thought it would be like that.

> I have attached /proc/interrupts for 2.6.35-rc4, once with pci=nomsi
> and once without, but again, I do not think this makes a difference :-/
> 
> > Also, do you have a link to this "Google suggestion"?
> 
> It was some german forum, a guy with completely different HW, but the
> same symptom. I thought trying out the option wouldn't hurt.
> 
> Maybe it came for example from http://lkml.org/lkml/2008/12/20/3
> originally.

I have a box where this problem is kind of reproducible, but it happens _very_
rarely.  Also I can't reproduce it on demand running suspend-resume in a tight
loop.  Are you able to reproduce it more regurarly?

Also, what kind of disk do you use?

Rafael