Re: [PATCH] Ignore DEBUGCTL MSRs

[Avi Kivity <avi@qumranet.com>]

Alexander Graf wrote:
>>
>>> +        pr_unimpl(vcpu, "%s: MSR_IA32_DEBUGCTLMSR 0x%llx, nop\n",
>>> +            __func__, data);
>>>   
>>
>> We can avoid the printout if data == 0, since we support that case 
>> fully.
>
> I was thinking a lot about that. Even though we support data == 0, 
> usually the kernel log output is useful for people trying to find if 
> something is cause a problem. If they see that DEBUGCTL gets set, but 
> won't see it getting unset, they'd get confused IMHO.
> So the current behavior is on purpose, but if you oppose to that idea, 
> please tell me.
>

Once it gets set, you can expect brokenness.  It doesn't matter if it 
gets unset later.  So IMO not printing on data == 0 is best: quiet on 
the cases we support, and loud on cases we don't.  So yes, I'd prefer it 
changed.


-- 
error compiling committee.c: too many arguments to function