Sean Christopherson <[email protected]> writes: > On Fri, Oct 24, 2025, Ackerley Tng wrote: >> Sean Christopherson <[email protected]> writes: >> > @@ -486,6 +488,7 @@ struct kvm_vm *__vm_create(struct vm_shape shape, >> > uint32_t nr_runnable_vcpus, >> > } >> > guest_rng = new_guest_random_state(guest_random_seed); >> > sync_global_to_guest(vm, guest_rng); >> > + sync_global_to_guest(vm, kvm_has_gmem_attributes); >> >> I ported this [1] except for syncing this value to the guest, because I >> think the guest shouldn't need to know this information, > > KVM selftests are about practically and testing, what information should or > shouldn't be available to a test from e.g. a safety perspective is completely > irrelevant. In fact, one of the biggest advantages of selftests over KUT is > that the guest side can know _exactly_ what's going on in the host. > > See the usage in 1850e3da4b03 ("KVM: selftests: Update > private_mem_conversions_test > to mmap() guest_memfd") from: > > https://github.com/sean-jc/linux.git x86/gmem_inplace > >> the host should decide what to do. I think, if the guests really need to know >> this, the test itself can do the syncing. > > Why force tests to do extra work, and potentially introduce subtle bugs due to > state being stale?
Adding it back. Thanks! This variable should be sync-able for TDX selftests as well since the value should be synced before the TD image is loaded.
