Re: [PATCH] [irq] Fix boot failure when irqaffinity is passed.

[Ingo Molnar]

* Rakib Mullick <rakib.mullick@xxxxxxxxx> wrote:

> When irqaffinity kernel param is passed in a CPUMASK_OFFSTACK=y build
> kernel, it fails to boot. zalloc_cpumask_var() cannot be used before
> initializing mm stuff (slab allocator) to allocate cpumask. So, use
> alloc_bootmem_cpumask_var(). Also in init_irq_default_affinity() removes
> unneeded ifdef, these ifdef conditions are handled at defination site.
> 
> Signed-off-by: Rakib Mullick <rakib.mullick@xxxxxxxxx>
> ---
>  kernel/irq/irqdesc.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
> index 982a357..db6380d 100644
> --- a/kernel/irq/irqdesc.c
> +++ b/kernel/irq/irqdesc.c
> @@ -27,7 +27,7 @@ static struct lock_class_key irq_desc_lock_class;
>  #if defined(CONFIG_SMP)
>  static int __init irq_affinity_setup(char *str)
>  {
> -	zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
> +	alloc_bootmem_cpumask_var(&irq_default_affinity);
>  	cpulist_parse(str, irq_default_affinity);
>  	/*
>  	 * Set at least the boot cpu. We don't want to end up with
> @@ -40,10 +40,8 @@ __setup("irqaffinity=", irq_affinity_setup);
>  
>  static void __init init_irq_default_affinity(void)
>  {
> -#ifdef CONFIG_CPUMASK_OFFSTACK
>  	if (!irq_default_affinity)
>  		zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
> -#endif
>  	if (cpumask_empty(irq_default_affinity))
>  		cpumask_setall(irq_default_affinity);
>  }

Not applied, because this patch causes the following build warning:

  kernel/irq/irqdesc.c:43:6: warning: the address of âirq_default_affinityâ will always evaluate as âtrueâ [-Waddress]

Also, please pick up the improved changelog below for the next version of the 
patch.

Thanks,

	Ingo

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