Test that conversion to private specifying the
KVM_SET_MEMORY_ATTRIBUTES2_ZERO flag returns -1 and sets errno to
EOPNOTSUPP.

Signed-off-by: Ackerley Tng <ackerleytng@google.com>
---
 .../testing/selftests/kvm/guest_memfd_conversions_test.c  | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tools/testing/selftests/kvm/guest_memfd_conversions_test.c b/tools/testing/selftests/kvm/guest_memfd_conversions_test.c
index 4ccd3d515bb26..c0abc69f15332 100644
--- a/tools/testing/selftests/kvm/guest_memfd_conversions_test.c
+++ b/tools/testing/selftests/kvm/guest_memfd_conversions_test.c
@@ -488,6 +488,21 @@ GMEM_CONVERSION_MULTIPAGE_TEST_INIT_SHARED(elevated_refcount, 4)
 	}
 }
 
+GMEM_CONVERSION_TEST_INIT_SHARED(convert_to_private_does_not_support_zero)
+{
+	const loff_t start_offset = 0;
+	loff_t error_offset = -1ul;
+	int ret;
+
+	ret = __gmem_set_private(t->gmem_fd, start_offset, nr_pages * page_size,
+				 &error_offset,
+				 KVM_SET_MEMORY_ATTRIBUTES2_ZERO);
+
+	TEST_ASSERT_EQ(ret, -1);
+	TEST_ASSERT_EQ(errno, EOPNOTSUPP);
+	TEST_ASSERT_EQ(error_offset, start_offset);
+}
+
 int main(int argc, char *argv[])
 {
 	TEST_REQUIRE(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SW_PROTECTED_VM));

-- 
2.53.0.1018.g2bb0e51243-goog