Re: [RFC, PATCH 2/24] i386 Vmi config

[Zachary Amsden <zach@vmware.com>]

Christoph Hellwig wrote:
> On Mon, Mar 13, 2006 at 10:00:27AM -0800, Zachary Amsden wrote:
>   
>> Introduce the basic VMI sub-arch configuration dependencies.  VMI kernels only
>> are designed to run on modern hardware platforms.  As such, they require a
>> working APIC, and do not support some legacy functionality, including APM BIOS,
>> ISA and MCA bus systems, PCI BIOS interfaces, or PnP BIOS (by implication of
>> dropping ISA support).  They also require a P6 series CPU.
>>     
>
> That's pretty bad because distributors need another kernel still.  At least
> a working APIC isn't quite as common today as it should.
>   

It doesn't need to be a fully functional APIC.  It just needs to not 
have one particular bug - Pentium processor erratum 11AP.  There is no 
reason that most of these requirements can't be dropped.  We used to 
have a lot more functionality and legacy support turned off, and we 
gradually turned it back on.  Turning on the BIOS interfaces will cause 
complications for a VMI kernel running in a hypervisor - since it can't 
invoke non-virtualized BIOS code.  So it does require a bit of 
conditional logic, which is pretty easy, but we haven't got around to 
doing yet.

Zach