Re: [PATCH v3 kvm/queue 11/16] KVM: Add kvm_map_gfn_range

[Sean Christopherson]

On Thu, Dec 23, 2021, Chao Peng wrote:
> This new function establishes the mapping in KVM page tables for a
> given gfn range. It can be used in the memory fallocate callback for
> memfd based memory to establish the mapping for KVM secondary MMU when
> the pages are allocated in the memory backend.

NAK, under no circumstance should KVM install SPTEs in response to allocating
memory in a file.   The correct thing to do is to invalidate the gfn range
associated with the newly mapped range, i.e. wipe out any shared SPTEs associated
with the memslot.