Re: [ANNOUNCE] 3.0.1-rt11

[Russell King - ARM Linux]

On Wed, Sep 07, 2011 at 11:25:29AM +0200, Thomas Gleixner wrote:
> This smells badly like the problem we've seen on x86 before. And
> looking at the arm SMP boot code:
> 
> asmlinkage void __cpuinit secondary_start_kernel(void)
> {
> 	.....
> 
> 	/*
> 	 * Give the platform a chance to do its own initialisation.
> 	 */
> 	platform_secondary_init(cpu);
> 
> 	/*
> 	 * Enable local interrupts.
> 	 */
> 	notify_cpu_starting(cpu);
> 	local_irq_enable();
> 
> Here we enable interrupts, but the CPU is neither online nor active.
> 
> 	local_fiq_enable();

That's intentional.  Some of the code below needs IRQs enabled.

I think we had this reported before and I got to the bottom of it - the
platform was doing something it shouldn't.  I don't remember the details,
maybe when all the emails come through I can see the original bug report
I'll remember.
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