BUG: spinlock recursion (sys_chdir, user_path_at, do_path_lookup ...)

[Uwe Kleine-König]

Hello Omar,

On Wed, Jan 12, 2011 at 02:59:39PM -0600, Ramirez Luna, Omar wrote:
> I picked this mail from google so I might be missing some recipients.
> 
> On Wed, 12 Jan 2011, Russell King - ARM Linux wrote:
> > On Wed, Jan 12, 2011 at 12:35:08PM +0000, Russell King - ARM Linux wrote:
> > > ARM doesn't implement save_stack_trace_regs() nor save_stack_trace_bp()
> > > so if the compiler referenced these, you'd have a kernel which doesn't
> > > link.  The only places that this symbol appears is:
> > >
> > > arch/x86/kernel/stacktrace.c:void save_stack_trace_regs(struct stack_trace *trac
> > > arch/x86/mm/kmemcheck/error.c:  save_stack_trace_regs(&e->trace, regs);
> > > include/linux/stacktrace.h:extern void save_stack_trace_regs(struct stack_trace
> > >
> > > So, if this is where your bisect decided was the problem, your bisect
> > > was faulty.
> >
> > BTW, a useful thing to do after a bisect is to return to the point in
> > the history where you first noticed the regression (so Linus' tip,
> > your tip, or whatever).  Then try reverting the commit which git bisect
> > _thinks_ is the cause of your problem and re-test that.
> >
> > If the problem is fixed, you have greater confidence that the commit is
> > the problem.
> 
> Reverting this commit (9c0729dc8062bed96189bd14ac6d4920f3958743 )
> didn't improve in my case.
Yeah, my bisect was screwed because I somehow changed .config in the
middle ...

You're on ARM, too?

> > If it made no difference, then you know that something else (maybe in
> > combination) is causing the problem.
> 
> I tried to narrow it down using the dump and another thread mentioning
> recent changes from "Nick" (might be Nick Piggin).
> 
> Reverting: fs: rcu-walk aware d_revalidate method
> commit: 34286d6662308d82aed891852d04c7c3a2649b16
I found that one, too, in the meantime.  Currently debugging that with
tglx on irc.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |