Re: [patch 3/5] x2apic, IR: cleanup panic() with nox2apic boot option

[Ingo Molnar <mingo@elte.hu>]

* Suresh Siddha <suresh.b.siddha@intel.com> wrote:

> Instead of panic() ignore the "nox2apic" boot option when BIOS has
> already enabled x2apic prior to OS handover.
> 
> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
> Cc: Weidong Han <weidong.han@intel.com>
> ---
> 
> Index: tip/arch/x86/kernel/apic/apic.c
> ===================================================================
> --- tip.orig/arch/x86/kernel/apic/apic.c
> +++ tip/arch/x86/kernel/apic/apic.c
> @@ -142,8 +142,12 @@ static int x2apic_preenabled;
>  static int disable_x2apic;
>  static __init int setup_nox2apic(char *str)
>  {
> -	if (x2apic_enabled())
> -		panic("Bios already enabled x2apic, can't enforce nox2apic");
> +	if (x2apic_enabled()) {
> +		pr_warning("Bios already enabled x2apic, "
> +			   "can't enforce nox2apic");

Btw., in such cases we dont break printk strings in the middle but 
ignore the checkpatch warning. I fixed it up in your patch.

The advantage is that if someone, based on a dmesg line, types:

   git grep Bios already enabled x2apic, can't enforce nox2apic

the right source code line will be found. In the broken-up-line case 
this wont work. (grep is fundamentally single-line)

	Ingo