Re: Linux v2.5.48

[William Lee Irwin III <wli@holomorphy.com>]

On Mon, Nov 18, 2002 at 07:30:37PM +0100, Manfred Spraul wrote:
> __cpu_up is called in the context of the boot cpu, not in the context of 
> the new cpu.
> I think this patch should keep the interrupts disabled until after
> smp_commenced is set. It's partially tested: bochs boots until all cpus
> are up and then crashes.
> I've tested the interrupt flag (pushfl;popfl), noone else enables them.

That's odd, this should (in theory) enable them:

void __init setup_secondary_APIC_clock(void)
{
        local_irq_disable(); /* FIXME: Do we need this? --RR */
        setup_APIC_timer(calibration_result);
        local_irq_enable();
}


> --- 2.5/arch/i386/kernel/smpboot.c	2002-11-04 23:30:27.000000000 +0100
> +++ build-2.5/arch/i386/kernel/smpboot.c	2002-11-18 19:19:38.000000000 +0100
> @@ -405,8 +405,6 @@
>  		clear_local_APIC();
>  	setup_local_APIC();
>  
> -	local_irq_enable();
> -
>  	/*
>  	 * Get our bogomips.
>  	 */
> @@ -449,6 +447,8 @@
>  	smp_callin();
>  	while (!test_bit(smp_processor_id(), &smp_commenced_mask))
>  		rep_nop();
> +
> +	local_irq_enable();
>  	setup_secondary_APIC_clock();
>  	if (nmi_watchdog == NMI_IO_APIC) {
>  		disable_8259A_irq(0);

I've booted this and it functions equivalently on my machines.


Bill