Re: [PATCH 0/2] KVM: MMU: support VMAs that got remap_pfn_range-ed

[Xiao Guangrong]

On 07/04/2016 11:33 PM, Neo Jia wrote:

> > > Sorry, I think I misread the "allocation" as "mapping". We only delay the
> > > cpu mapping, not the allocation.
> >
> > So how to understand your statement:
> > "at that moment nobody has any knowledge about how the physical mmio gets virtualized"
> >
> > The resource, physical MMIO region, has been allocated, why we do not know the physical
> > address mapped to the VM?
>
> > From a device driver point of view, the physical mmio region never gets allocated until
> the corresponding resource is requested by clients and granted by the mediated device driver.

Hmm... but you told me that you did not delay the allocation. :(

So it returns to my original question: why not allocate the physical mmio region in mmap()?