pub fn host_nested_virt() -> NestedVirtSupportExpand description
Probes nested-virtualization support on this host.
Cached on macOS, where this is a fixed hardware/OS property that
cannot change while the process lives. Re-probed on every call
elsewhere: on Linux the answer depends on the kvm_intel/kvm_amd
module being loaded, and this function is reachable — via the sandbox
capability gate — before any VM has ever booted (in particular under
--no-linux-vm, where nothing in this process ever opens /dev/kvm).
A query that lands before the module autoloads would otherwise cache a
false negative for the rest of the process’s life.