Re: [Qemu-devel] Re: [PATCH 16/23] pci: pcie host and mmcfg support.

[Akio Takebe]

>> So I thought about this some more, and I think that this change
>> in unnecessary. PCI Express adds support for extended 4K
>> configuration space, but the only thing that must reside
>> there is the optional advanced error reporting capability,
>> which I don't think we'll need to implement, ever.
>>
>> Everything else can reside in the first 256 bytes, just as for regular
>> PCI. And pci code already returns 0 for accesses outside the first 256
>> bytes, so express specific code is necessary.
>
>I agree with you for emulated PCI express device
>(which doesn't exist for now). However I oppose it for other reason.
>
>My purpose is to direct attach PCIe device to a guest including
>AER emulation somehow.
>When direct attaching PCIe native device to a guest,
>we don't have any control on how its configuration space is used.
>When an error is reported on host via AER, I'd like to pass 
>the error to guest in some manner. So I want AER too in a sense.
I also want AER feature. In this PCIe emulator codes,
PCIe features like AER is highlight.
If we can use AER, this pcie emulator is very worthwhile, I think.

Best Regards,

Akio Takebe