Re: [Qemu-devel] [RFC] Memory API

[Jan Kiszka]

On 2011-05-19 15:52, Anthony Liguori wrote:
> On 05/19/2011 03:30 AM, Jan Kiszka wrote:
>> On 2011-05-19 10:26, Gleb Natapov wrote:
>>> On Wed, May 18, 2011 at 09:27:55PM +0200, Jan Kiszka wrote:
>>>>> if an I/O is to the APIC page,
>>>>>     it's handled by the APIC
>>>>
>>>> That's not that simple. We need to tell apart:
>>>>   - if a cpu issued the request, and which one =>  forward to APIC
>>> And cpu mode may affect where access is forwarded to. If cpu is in SMM
>>> mode access to frame buffer may be forwarded to a memory (depends on
>>> chipset configuration).
>>
>> So we have a second use case for CPU-local I/O regions?
>>
>> I wonder if only a single CPU can enter SMM or if all have to.
> 
> For the i440fx, it's a chipset register (not a per-CPU register).

There are two sources: the chipset register and the mode of the first
CPU. Both things were apparently incorrectly merged into the
minimalistic i440fx model.

Jan

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