On 25/07/2018 21:43, speck for Andrew Cooper wrote:
>>  	case MSR_IA32_UCODE_REV:
>> -		rdmsrl(msr->index, msr->data);
>
> You'll be wanting a break in here.
> 
>> +	case MSR_IA32_ARCH_CAPABILITIES:
>> +		rdmsrl_safe(msr->index, &msr->data);
>>  		break;

No, this is a fallthrough.  This patch is unrelated to L1TF, and I'm
including it just because the branch is based on 4.18-rc1.  See the
patch #4 for the actual patch that introduces L1TF handling, and indeed
it doesn't rely on fallthrough anymore.  The code there becomes:

 	case MSR_IA32_ARCH_CAPABILITIES:
		msr->data = kvm_get_arch_capabilities();
		break;
	case MSR_IA32_UCODE_REV:
 		rdmsrl_safe(msr->index, &msr->data);
 		break;

but not yet.  Thanks,

Paolo