Re: [PATCH] x86/MCE: bypass uninitialized vcpu in vMCE injection

[Kai Huang <kai.huang@linux.intel.com>]

On 05/07/2014 04:23 PM, Jan Beulich wrote:
>>>> On 07.05.14 at 09:29, <kai.huang@linux.intel.com> wrote:
>> --- a/xen/arch/x86/cpu/mcheck/vmce.c
>> +++ b/xen/arch/x86/cpu/mcheck/vmce.c
>> @@ -356,6 +356,10 @@ int inject_vmce(struct domain *d, int vcpu)
>>           if ( vcpu != VMCE_INJECT_BROADCAST && vcpu != v->vcpu_id )
>>               continue;
>>   
>> +        /* In case of broadcasting, don't inject to uninitialized VCPU */
>> +        if ( vcpu == VMCE_INJECT_BROADCAST && !v->is_initialised )
>> +            continue;
>> +
> Conceptually fine, but mechanically in need of improvement: Please
> fold the check with the previous one, to avoid checking for
> VMCE_INJECT_BROADCAST twice.
>
> I'd do this as
>
>          if ( vcpu != VMCE_INJECT_BROADCAST ? vcpu != v->vcpu_id
>                                             : !v->is_initialised )
>              continue;
Thanks for comments. In this case, is it OK to you to add below comments 
just before the if statement? I think it's better to keep the comments 
somewhere.

	/* In case of broadcasting, don't inject to uninitialized VCPU */
	if ( vcpu != VMCE_INJECT_BROADCAST ? vcpu != v->vcpu_id
                                            : !v->is_initialised )
             continue;

Thanks,
-Kai
>
> but if you prefer some other style (like nested if/else), that would
> be fine with me too.
>
> Also please don't forget to also Cc the second x86/MCE maintainer.
>
> Jan
>