Re: 2.6.29-rc3: weird process after resume

[Andrew Morton <akpm@linux-foundation.org>]

On Wed, 4 Feb 2009 18:31:42 -0800 Andrew Morton <akpm@linux-foundation.org> wrote:

> On Wed, 04 Feb 2009 17:45:13 -0800 Alex Romosan <romosan@sycorax.lbl.gov> wrote:
> 
> > Andrew Morton <akpm@linux-foundation.org> writes:
> > 
> > > On Wed, 04 Feb 2009 09:25:20 -0800
> > > Alex Romosan <romosan@sycorax.lbl.gov> wrote:
> > >
> > >> this is on a thinkpad t61p with an intel core2 cpu. i just noticed
> > >> that after resuming from suspending to memory i get a weirdly named
> > >> process. i did a ps before and after and the only difference was that
> > >> before i had this process:
> > >> 
> > >>   [hda0/1]
> > >> 
> > >> and after this one:
> > >> 
> > >>   [__?__;??____D__"?______]
> > >> 
> > >> with everything else being the same. the laptop seems to be working
> > >> fine and the problem could have been there for a while but i just
> > >> didn't notice it. i am including my .config file. let me know if you
> > >> need anything else.
> > >
> > > Were earlier kernels OK?  If so, which version?
> > 
> > i just tried 2.6.28 and there was no [hda0] kernel thread. 2.6.29-rc1
> > and rc2 never resumed from suspend so i couldn't really try it.
> > 
> > > What the heck is that kernel thread anyway?  It looks like something
> > > derived from an IDE device.
> > 
> > i have no idea. hda is the cdrom (the disk is sata and shows up as
> > sda).
> > 
> 
> <rummages through a 68MB diff for a while>
> 
> <finds a plum>
> 
> +       snprintf(qname, sizeof(qname), "hda%d", card->number);
> +       bus->workq = create_workqueue(qname);
> +       if (!bus->workq) {
> +               snd_printk(KERN_ERR "cannot create workqueue %s\n", qname);
> +               kfree(bus);
> +               return -ENOMEM;
> +       }
> 
> so it's not IDE after all.
> 
> commit 6acaed38a32e8571e92cfc832b971f9e4450c207
> Author:     Takashi Iwai <tiwai@suse.de>
> AuthorDate: Mon Jan 12 10:09:24 2009 +0100
> Commit:     Takashi Iwai <tiwai@suse.de>
> CommitDate: Mon Jan 12 10:33:56 2009 +0100
> 
>     ALSA: hda - Use own workqueue
> 

btw.  Please use create_singlethread_workqueue() if at all possible.  I
don't think we need a thread per CPU here.