Re: [PATCH 1/2] x86/mce: Include the PPIN in machine check records when it is available

From: Andi Kleen
Date: Fri Nov 18 2016 - 12:03:09 EST


Borislav Petkov <bp@xxxxxxx> writes:
>
>> @@ -2134,8 +2140,37 @@ static int __init mcheck_enable(char *str)
>> }
>> __setup("mce", mcheck_enable);
>>
>> +static void mcheck_intel_ppin_init(void)
>
> So this functionality could all be moved to arch/x86/kernel/cpu/intel.c
> where you could set an artificial X86_FEATURE_PPIN and get rid of the
> have_ppin var.


That means that a tiny kernel that compiles out machine check
functionality has this unnecessary code.

In general it doesn't make any sense to define a FEATURE flag for
a single user. It's better to just check it where it is needed.

-Andi