Re: PROBLEM: 3.0-rc kernels unbootable since -rc3

Paul E. McKenney
2011-07-11T20:15:23Z

On Mon, Jul 11, 2011 at 03:30:22PM -0400, Konrad Rzeszutek Wilk wrote:
> >
> > Hmmm... Does the stall repeat about every 3.5 minutes after the first stall?
>
> Starting Configure read-only root support...
> [ 81.335070] INFO: rcu_sched_state detected stalls on CPUs/tasks: { 0} (detected by 3, t=60002 jiffies)
> [ 81.335091] sending NMI to all CPUs:
> [ 261.367071] INFO: rcu_sched_state detected stalls on CPUs/tasks: { 0} (detected by 3, t=240034 jiffies)
> [ 261.367092] sending NMI to all CPUs:
> [ 441.399066] INFO: rcu_sched_state detected stalls on CPUs/tasks: { 0} (detected by 3, t=420066 jiffies)
> [ 441.399089] sending NMI to all CPUs:

OK, then the likely cause is something hanging onto the CPU. Do the later
stalls also show stack traces? If so, what shows up?

(Documentation/RCU/stallwarn.txt for more info on this.)

> >
> > One thing to try would be to disable CONFIG_RCU_FAST_NO_HZ. I wouldn't
> > expect this to have any effect, but might be worth a try. It is really
>
> Did not help.

Well, I guess it met my expectations. Thank you for trying it!

Thanx, Paul

> > intended for small battery-powered systems.
> >