Re: [PATCH RESEND] fix WARNING: at kernel/cpu/idle.c:96

[Thomas Gleixner <tglx@linutronix.de>]

On Fri, 14 Jun 2013, James Bottomley wrote:

> >From 48bbf44a96676ce6f520a408378730c976e9a11e Mon Sep 17 00:00:00 2001
> From: James Bottomley <JBottomley@Parallels.com>
> Date: Wed, 8 May 2013 14:05:34 -0700
> Subject: [PATCH] [PARISC] fix WARNING: at kernel/cpu/idle.c:96
> 
> On PA-RISC (and presumably any other arch that doesn't implement its own
> arch_cpu_idle), we get this spurious boot warning.  The problem is that the
> way the idle task is selected initially using the weak arch_cpu_idle() in
> idle.c causes us to enter this place once with interrupts enabled.  Fix this
> by disabling interrupts in the weak arch_cpu_idle() code.
> 
> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
> Cc: stable@vger.kernel.org

What's the stable tag for? This code got merged in 3,10, so stable is
totally irrelevant.

> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
> 
> ---
> 
> Thomas, I'm getting a bit impatient: this is a clear bug in the cpu idle
> code and we keep getting reports of this as a boot crash on parisc.  If
> you don't push it through your tree, I'll take it through the parisc
> one.

Hold your breath. I was not even CC'ed on the original patch and I
admit that I ignored the patch which starts with [PARISC].

If the subject line would have started with [idle], [core/idle] I
definitely would have paid attention.

Aside of that the rest of the subject line is just annoyingly
sloppy. We do not fix a WARNING. That's not what this patch is
about. The patch fixes a problem which got introduced with the idle
rework, period.

I'll pick it up and fix the changelog.

Thanks,

	tglx

> 
> diff --git a/kernel/cpu/idle.c b/kernel/cpu/idle.c
> index d5585f5..0a4d11e 100644
> --- a/kernel/cpu/idle.c
> +++ b/kernel/cpu/idle.c
> @@ -58,6 +58,7 @@ void __weak arch_cpu_idle_dead(void) { }
>  void __weak arch_cpu_idle(void)
>  {
>  	cpu_idle_force_poll = 1;
> +	local_irq_enable();
>  }
>  
>  /*
> 
> 
>