Re: 2.6.24-git2: Oracle 11g VKTM process enters R state on startup and is unkillable [still broken in 2.6.25-rc1]

[Ingo Molnar <mingo@elte.hu>]

* Ingo Molnar <mingo@elte.hu> wrote:

> no, they were not lost, they just didnt pass QA here (they crashed on 
> a particularly hard to debug 8-way box i have) and Peter worked on 
> that queue of fixes up until today to get it really correct. Could you 
> check:
> 
>    git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched.git
> 
> combo patch below as well - whichever you prefer. The shortlog can be 
> found below as well - but i dont yet consider this pullable, i'd like 
> it to see pass a full night of randconfig tests on my test-systems.

ok, we just found the reason for the 8-way crash, the delta fix from 
Peter is below if any of you have tried the previous combo patch. 
Updated sched.git as well, new HEAD is 
fec13e45305d69fd0bd23b30bd05a0a42cf341f8.

	Ingo

Index: linux-2.6/kernel/sched.c
===================================================================
--- linux-2.6.orig/kernel/sched.c
+++ linux-2.6/kernel/sched.c
@@ -219,6 +219,10 @@ static void start_rt_bandwidth(struct rt
 	if (rt_b->rt_runtime == RUNTIME_INF)
 		return;
 
+	if (hrtimer_active(&rt_b->rt_period_timer))
+		return;
+
+	spin_lock(&rt_b->rt_runtime_lock);
 	for (;;) {
 		if (hrtimer_active(&rt_b->rt_period_timer))
 			break;
@@ -229,6 +233,7 @@ static void start_rt_bandwidth(struct rt
 			      rt_b->rt_period_timer.expires,
 			      HRTIMER_MODE_ABS);
 	}
+	spin_unlock(&rt_b->rt_runtime_lock);
 }
 
 #ifdef CONFIG_RT_GROUP_SCHED