Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.6.8

[Mark_H_Johnson]

>hm, this one is an extremely weird deadlock - the NMI watchdog detected
>a _user-space_ deadlock - i.e. the "cpu_burn" user-space code disabled
>interrupts for more than ~5 seconds? Sounds quite unlikely and the
>EFLAGS register also directly contradicts it, it has 0x200 set so
>interrupts are enabled!

Very unlikely - cpu_burn.c (all of it...)

int main() {
  while (1) {  }
  return 1;
}

No - it did not disable interrupts.

>The only other way for the NMI watchdog to
>trigger is if for whatever reason the local APIC timer interrupts are
>not getting through and the NMI ticks (which come via a different
>interrupt pin) get through.

The other symptoms I was seeing appeared to be timer related
 - never returned from "sleep 1s" in the shell script
 - "ps -fe" worked fine, but "top" did not
You may be on to something here.

  --Mark

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/