Re: [Qemu-devel] [PATCH v2 1/5] i386: Add support for IA32_PRED_CMD and IA32_ARCH_CAPABILITIES MSRs

[Paolo Bonzini]

On 03/07/2018 13:07, Robert Hoo wrote:
>>      FEAT_XSAVE_COMP_LO, /* CPUID[EAX=0xd,ECX=0].EAX */
>>      FEAT_XSAVE_COMP_HI, /* CPUID[EAX=0xd,ECX=0].EDX */
>> +    FEATURE_WORDS_NUM_CPUID,
>> +    FEATURE_WORDS_FIRST_MSR = FEATURE_WORDS_NUM_CPUID,
>> +    FEAT_MSR_ARCH_CAPABILITIES = FEATURE_WORDS_FIRST_MSR,
>>      FEATURE_WORDS,
>> };
>>
>> #define FEATURE_WORDS_NUM_MSRS (FEATURE_WORDS - \
>>                                 FEATURE_WORDS_FIRST_MSR)
>>
>> Then the existing loops that use FeatureWordInfo can go up to
>> FEATURE_WORDS_NUM_CPUID.
> Emm... Understand your point now. It is a little risky, all references
> to FEATURE_WORDS need to be updated carefully.
> OK, let me try to think in this way.
> Perhaps, I'll need to define a new 'struct FeautureWordMsrInfo' to
> describe feature words from MSR, in parallel to current FeatureWordInfo
> (or better rename it to FeatureWordCpuidInfo).

Yes, probably.  The plan seems fine.

Paolo