Re: [PATCH RFC 04/10] intel_iommu: Second Stage Access Dirty bit support

[Joao Martins]

On 4/29/22 03:26, Jason Wang wrote:
> On Fri, Apr 29, 2022 at 5:14 AM Joao Martins <joao.m.martins@oracle.com> 
> wrote:
>> @@ -3693,7 +3759,8 @@ static void vtd_init(IntelIOMMUState *s)
>>
>>      /* TODO: read cap/ecap from host to decide which cap to be exposed. */
>>      if (s->scalable_mode) {
>> -        s->ecap |= VTD_ECAP_SMTS | VTD_ECAP_SRS | VTD_ECAP_SLTS;
>> +        s->ecap |= VTD_ECAP_SMTS | VTD_ECAP_SRS | VTD_ECAP_SLTS |
>> +                   VTD_ECAP_SLADS;
>>      }
> 
> We probably need a dedicated command line parameter and make it compat
> for pre 7.1 machines.
> 
> Otherwise we may break migration.

I can gate over an 'x-ssads' option (default disabled). Which reminds me that I 
probably
should rename to the most recent mnemonic (as SLADS no longer exists in 
manuals).

If we all want by default enabled I can add a separate patch to do so.

        Joao