Re: [Qemu-devel] Seabios dislikes -M isapc

[Anthony Liguori]

On 02/09/2010 06:27 PM, malc wrote:
> APIC is almost as good as useless without ACPI and we have a switch to
> disable that.
>    

Which is another thing that I'm not sure it all that useful to have.

> > Firmware is really hard to implement if you have to deal with supporting
> > multiple chipsets.
> >
> > Also, if we don't have a workload that actually needs isapc, that suggests
> > that there's no real way to test that isapc doesn't have non-ISA things creep
> > into it.
> >
> > Given that, I'm inclined to suggest that we mark isapc as deprecated, give
> > people some time to comment on it, and then provided that we still don't think
> > it's necessary, change isapc to simply use isa devices while still using a PCI
> > chipset.
> >      
> Not to comment, to give hard evidence that something is working with isapc
> and doesn't otherwise, in which case it must stay.
>    

Yes.  If someone can produce a workload that requires isapc[1], I'm all 
for continuing to support it.

[1] Very specifically, I mean requires -M isapc to only emulate an ISA 
bus and not emulate an ISA bus via a bridge in the PIIX chipset.  We 
will always need an -M isapc that only uses ISA devices instead of PCI 
devices.  However, if we can use a PCI chipset in -M isapc, we can 
express the differences entirely via qdev.

Regards,

Anthony Liguori