diff --git a/lib/bitlk/bitlk.c b/lib/bitlk/bitlk.c
index c3c01e4a..c09eff30 100644
--- a/lib/bitlk/bitlk.c
+++ b/lib/bitlk/bitlk.c
@@ -1431,24 +1431,15 @@ out:
 
 int BITLK_activate_by_volume_key(struct crypt_device *cd,
 				 const char *name,
-				 const char *volume_key,
-				 size_t volume_key_size,
+				 struct volume_key *vk,
 				 const struct bitlk_metadata *params,
 				 uint32_t flags)
 {
-	int r = 0;
-	struct volume_key *open_fvek_key = NULL;
+	int r;
 
 	r = _activate_check(cd, params);
 	if (r)
 		return r;
 
-	open_fvek_key = crypt_alloc_volume_key(volume_key_size, volume_key);
-	if (!open_fvek_key)
-		return -ENOMEM;
-
-	r = _activate(cd, name, open_fvek_key, params, flags);
-
-	crypt_free_volume_key(open_fvek_key);
-	return r;
+	return _activate(cd, name, vk, params, flags);
 }
diff --git a/lib/bitlk/bitlk.h b/lib/bitlk/bitlk.h
index f1756832..82a89d94 100644
--- a/lib/bitlk/bitlk.h
+++ b/lib/bitlk/bitlk.h
@@ -124,8 +124,7 @@ int BITLK_activate_by_passphrase(struct crypt_device *cd,
 
 int BITLK_activate_by_volume_key(struct crypt_device *cd,
 				 const char *name,
-				 const char *volume_key,
-				 size_t volume_key_size,
+				 struct volume_key *vk,
 				 const struct bitlk_metadata *params,
 				 uint32_t flags);
 
diff --git a/lib/setup.c b/lib/setup.c
index 8784a4d8..6c89781e 100644
--- a/lib/setup.c
+++ b/lib/setup.c
@@ -5623,8 +5623,7 @@ static int _activate_by_volume_key(struct crypt_device *cd,
 				       cd->u.integrity.sb_flags);
 	} else if (isBITLK(cd->type)) {
 		assert(!external_key);
-		r = BITLK_activate_by_volume_key(cd, name, vk->key, vk->keylength,
-						 &cd->u.bitlk.params, flags);
+		r = BITLK_activate_by_volume_key(cd, name, vk, &cd->u.bitlk.params, flags);
 	} else if (isFVAULT2(cd->type)) {
 		assert(!external_key);
 		assert(crypt_volume_key_get_id(vk) == KEY_VERIFIED);