Re: rcu: BUG: spinlock recursion on CPU#3, trinity-child19/5970

["Paul E. McKenney" <paulmck@linux.vnet.ibm.com>]

On Wed, Jul 04, 2012 at 04:54:51PM +0200, Sasha Levin wrote:
> On Mon, 2012-07-02 at 07:59 -0700, Paul E. McKenney wrote:
> > On Mon, Jul 02, 2012 at 04:36:53PM +0200, Sasha Levin wrote:
> > > Looks like its running fine for a bit now (~10 min). I'll ping if
> > > anything changes, but on the other tests it has usually failed at this
> > > point.
> > If testing goes well (both yours and mine), I will be submitting this
> > as urgent, since it is a 3.5 regression.  If they don't take it, I will
> > queue it for 3.6.
> 
> 2 days later, and this didn't reproduce. I think we can say it's solved.

Very good, and thank you very much for all your testing efforts!

I have added a ten-microsecond delay to __rcu_read_unlock() under a
new CONFIG_RCU_PROVE_DELAY, and have added this to my testing regimen.
And I guess I have also added it in a probabilistic manner to the various
randconfig testing out there.  ;-)

Or will have when it hits mainline, probably 3.7.

							Thanx, Paul