Re: 2.6.23 regression: do_nanosleep will not return

[Peter Zijlstra <peterz@infradead.org>]

On Mon, 2007-10-08 at 17:01 +0200, Bernd Schubert wrote:
> On Monday 08 October 2007 16:32:52 Rik van Riel wrote:
> > On Mon, 08 Oct 2007 15:20:26 +0200
> >
> > Bernd Schubert <bs@q-leap.de> wrote:
> > > Bernd Schubert wrote:
> > > > we have a system here were e.g. "sleep 1" will never finish. This
> > > > is an issue of 2.6.23, on all older kernel versions it did work
> > > > fine.
> > > >
> > > > Seems to hang in do_nanosleep()
> > >
> > > Update: Enabling hpet in the bios and setting clocksource=hpet as
> > > command line parameter will fix it, but still its not nice that
> > > something that worked without a problem in 2.6.22 and below suddenly
> > > doesn't work in 2.6.23.
> >
> > Which timer source is in use when the system hangs?
> 
> Well, not the systems hangs, only processes running nanosleep. Well, since the 
> system is booted diskless, one of the very first commands is to 
> run "/etc/init.d/portmap start", which has a sleep call in its script and so 
> it will halt the boot process.
> 
> The problematic timer source is acpi_pm. Its also interesting that setting the 
> timer source 
> via /sys/devices/system/clocksource/clocksource0/current_clocksource won't 
> fix that problem. Only the boot option clocksource={other than acpi_pm} does 
> help.

Maybe Thomas knows..