Re: [Qemu-devel] [PATCH V19 1/7] Support for TPM command line options

[Stefan Berger <stefanb@linux.vnet.ibm.com>]

On 11/08/2012 10:52 AM, Corey Bryant wrote:
>
>
> On 10/24/2012 03:06 PM, Stefan Berger wrote:
>> On 09/27/2012 10:12 AM, Corey Bryant wrote:
>>>
>>>
>>> On 06/04/2012 03:37 PM, Stefan Berger wrote:
>>
>>>> +    if (!QLIST_EMPTY(&tpm_backends)) {
>>>> +        error_report("Only one TPM is allowed.\n");
>>>> +        return 1;
>>>> +    }
>>>
>>> A list of tpm_backends is maintained and walked in a few places, but
>>> only one is allowed to be added to the list.  Will it ever make sense
>>> to enable multiple backends at one time?
>>>
>>
>> A list is also returned through the monitor. This list can at the moment
>> only have maximum of one entry. I would keep that list there unless
>> someone else opposes. It may be possible to create different types of
>> hardware emulation interfaces or simply replicate the TPM TIS at
>> different addresses. So I cannot say whether it will 'ever make sense'
>> to do that but I'd rather keep the opportunity there than close it and
>> with that also let the monitor return a list of items rather than a
>> single item.
>>
>> I removed the processing of the lists in this part of the code at least.
>>
>
> Ok and it doesn't hurt to keep the list processing.  In that case you 
> might as well keep the list processing code everywhere that you 
> already have it.
>

I was only going to keep it in the monitor part now...
+ */
>>>> +int tpm_config_parse(QemuOptsList *opts_list, const char *optarg)
>>>> +{
>>>> +    QemuOpts *opts;
>>>> +
>>>> +    if (strcmp("none", optarg) != 0) {
>>>
>>> What's the point of supporting "-tpmdev none"?
>>>
>>
>> Removed.
>>
>
> There must have been a reason you added it in the first place that I'm 
> just not aware of.  Did someone else suggest adding it?

Not that I can remember.The option would have been useful if every VM by 
default had a TPM, similar to the physical world today, but it's 
unlikely that this will happen.


Regards,
     Stefan