[PATCH] ARM: Fix "BUG: scheduling while atomic: swapper/0/0x00000002"

[Sundar R IYER]

Hi Santosh/Russell,

>Hmm, I don't think this is how we should be solving this problem.
>x86 calls init_idle() on the idle task when it's re-used, and this
>resets the preempt count amongst other things.  So maybe we want to
>do this instead in the __cpu_up path:

The following patch fixes the dump messages at my end during re-onlining the offline CPU.

diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 577543f..ee1d608 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -86,6 +86,9 @@ int __cpuinit __cpu_up(unsigned int cpu)
                                                return PTR_ERR(idle);
                                }
                                ci->idle = idle;
+              } else {
+                              /* fix any preempt leaks whilst going down */
+                              init_idle(idle, cpu);
                }

Please let me know if this is alright.

Thanx!
Sundar