[OpenBIOS] Qemu, OpenBIOS, and HostID

[Mark Cave-Ayland]

On 28/12/13 05:26, Tarl Neustaedter wrote:

> On 2013-Dec-27, 18:53 , Nick Couchman wrote:

>> Understood, but a virtual environment is a little bit different, since
>> the only serial number is going to be some sort of UUID that is
>> generated either at VM start time or is generated and then maintained
>> in a config file. MAC addresses can be customized for VMs, as well.
>> Clearly 80000000 isn't a valid hostid, so what should OpenBIOS and/or
>> Qemu be doing, here?
>>
>
> I'd suggest that instead of h# 8000.0000, you should use h# 8012.3456 -
> that's the value we use when debugging hardware which doesn't have the
> idprom set up. Supposedly, nothing actually looks at the serial number
> in the hostid, but it's that "supposedly" which worries me.

Okay that's something that's fairly easy to do. My main questions would be:

i) if nothing looks at hostid, then would it matter that it is all zeros?

ii) if we do set it to 8012.3456 then if something did happen to check 
hostid then would it detect this special magic number and start to 
behave differently? (e.g. kernels detecting prototype hardware)

> You might also check that the system mac address is getting set up
> correctly. I know there are unexpected places that it gets used (certain
> SCSI drivers, for example).

Hmmm that's a good point actually. I don't believe that we currently set 
the MAC address property under /options.


ATB,

Mark.