sched: Disable scheduler warnings during oopses

The panic-on-framebuffer code seems to cause a schedule
to occur during an oops. This causes a bunch of extra
spew as can be seen in:

   https://bugzilla.redhat.com/attachment.cgi?id=549230

Don't do scheduler debug checks when we are oopsing already.
Signed-off-by: NDave Jones <davej@redhat.com>
Link: http://lkml.kernel.org/r/20111222213929.GA4722@redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

kernel/sched/core.c

@@ -3077,6 +3077,9 @@ static noinline void __schedule_bug(struct task_struct *prev)
 {
 	struct pt_regs *regs = get_irq_regs();
 
+	if (oops_in_progress)
+		return;
+
 	printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n",
 		prev->comm, prev->pid, preempt_count());