Re: sleeping functions called in invalid context during resume

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

On Friday, 17 November 2006 07:52, Ingo Molnar wrote:
> 
> * Stephen Hemminger <shemminger@osdl.org> wrote:
> 
> > > > BUG: sleeping function called from invalid context at drivers/base/power/resume.c:99
> > > > in_atomic():1, irqs_disabled():0
> > > > 
> > > > Call Trace:  
> > > >  [<ffffffff80266117>] show_trace+0x34/0x47
> > > >  [<ffffffff8026613c>] dump_stack+0x12/0x17
> > > >  [<ffffffff803734e5>] device_resume+0x19/0x51
> > > >  [<ffffffff80292157>] enter_state+0x19b/0x1b5
> > > >  [<ffffffff802921cf>] state_store+0x5e/0x79
> > > >  [<ffffffff802cc157>] sysfs_write_file+0xc5/0xf8
> > > >  [<ffffffff80215059>] vfs_write+0xce/0x174
> > > >  [<ffffffff802159a5>] sys_write+0x45/0x6e
> > > >  [<ffffffff802593de>] system_call+0x7e/0x83  
> > > > DWARF2 unwinder stuck at system_call+0x7e/0x83
> > > > 
> > 
> > Ingo, the later version of your lockdep patch (with the x86_64 fix), 
> > worked. There is nothing locked during these errors.
> > 
> > The problem was the APIC error is leaving preempt-disabled.
> 
> ah, that could be the case - do you have a fix-patch for that?
> 
> preempt-disabled leaks are only caught via CONFIG_PREEMPT_TRACE (not via 
> lockdep), which debug feature you can find in the -rt tree:
> 
>   http://redhat.com/~mingo/realtime-preempt/
> 
> (there's no easy standalone patch for now.)
> 
> it will be enabled if you select CONFIG_DEBUG_PREEMPT.
> 
> > I have no idea what causes:
> > 
> > APIC error on CPU0: 00(00)
> > 
> > Is it an ACPI problem?
> 
> a 00 error code? Never seen that ... How frequently does it happen?

On my x86-64 boxes the "APIC error on CPU0" message appears on every resume,
but it doesn't seem to be related to any visible problems.

It's been there forever, AFAICT.

Greetings,
Rafael


-- 
You never change things by fighting the existing reality.
		R. Buckminster Fuller