+Vipin Sharma
On Wed, Jan 31, 2024 at 4:21 PM Sean Christopherson <seanjc@xxxxxxxxxx> wrote:
> On Mon, Jan 22, 2024, isaku.yamahata@xxxxxxxxx wrote:
>
> The real reason for this drive-by pseudo-review is that I am hoping/wishing we
> can turn this into a generic KVM ioctl() to allow userspace to pre-map guest
> memory[*].
>
> If we're going to carry non-trivial code, we might as well squeeze as much use
> out of it as we can.
>
> Beyond wanting to shove this into KVM_MEMORY_ENCRYPT_OP, is there any reason why
> this is a VM ioctl() and not a vCPU ioctl()? Very roughly, couldn't we use a
> struct like this as input to a vCPU ioctl() that maps memory, and optionally
> initializes memory from @source?
>
> struct kvm_memory_mapping {
> __u64 base_gfn;
> __u64 nr_pages;
> __u64 flags;
> __u64 source;
> }
>
> TDX would need to do special things for copying the source, but beyond that most
> of the code in this function is generic.
>
> [*] https://lore.kernel.org/all/65262e67-7885-971a-896d-ad9c0a760907@xxxxxxxxx
We would also be interested in such an API to reduce the guest
performance impact of intra-host migration.
