Re: [PATCH] kvm, x86: Properly check whether a pfn is an MMIO or not

[Paolo Bonzini]

On 22/06/2016 04:34, KarimAllah Ahmed wrote:
> pfn_valid check is not sufficient because it only checks if a page has a struct
> page or not, if for example "mem=" was passed to the kernel some valid pages
> won't have a struct page. This means that if guests were assigned valid memory
> that lies after the mem= boundary it will be passed uncached to the guest no
> matter what the guest caching attributes are for this memory.

How can you pass memory after the mem= boundary to the guest?

Paolo