Re: [PATCH v14 13/22] KVM: selftests: Support guest_memfd in-place conversion

[Xiaoyao Li]

On 7/23/2026 7:13 AM, Lisa Wang wrote:
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> index 4a48c4b42095..e547ea341ff7 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> @@ -484,8 +484,10 @@ struct kvm_vm *__vm_create(struct vm_shape shape, u32 nr_runnable_vcpus,
>   	u64 nr_pages = vm_nr_pages_required(shape.mode, nr_runnable_vcpus,
>   						 nr_extra_pages);
>   	struct userspace_mem_region *slot0;
> +	u64 gmem_flags = 0;
>   	struct kvm_vm *vm;
> -	int i, flags;
> +	int flags = 0;
> +	int i;
>   
>   	kvm_set_files_rlimit(nr_runnable_vcpus);
>   
> @@ -495,14 +497,20 @@ struct kvm_vm *__vm_create(struct vm_shape shape, u32 nr_runnable_vcpus,
>   	vm = ____vm_create(shape);
>   
>   	/*
> -	 * Force GUEST_MEMFD for the primary memory region if necessary, e.g.
> -	 * for CoCo VMs that require GUEST_MEMFD backed private memory.
> +	 * Force GUEST_MEMFD for the primary memory region if necessary, and
> +	 * initialize it as shared if in-place conversion is support, so the
> +	 * selftest framework can populate it exactly like other memory
> +	 * providers.
>   	 */
> -	flags = 0;
> -	if (is_guest_memfd_required(shape))
> +	if (is_guest_memfd_required(shape)) {
>   		flags |= KVM_MEM_GUEST_MEMFD;
> +		if (kvm_has_gmem_attributes)
> +			gmem_flags |= GUEST_MEMFD_FLAG_INIT_SHARED |
> +				      GUEST_MEMFD_FLAG_MMAP;
> +	}
>   
> -	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, nr_pages, flags);
> +	vm_mem_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, nr_pages, flags,
> +		   -1, 0, gmem_flags);
>   	for (i = 0; i < NR_MEM_REGIONS; i++)
>   		vm->memslots[i] = 0;

IMO, this diff belongs to the gmem in-place series.