diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index f036b4c..2393d2a 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -105,7 +105,8 @@
 		status->data_version = data_version;
 		if (vnode && !test_bit(AFS_VNODE_UNSET, &vnode->flags)) {
 			_debug("vnode modified %llx on {%x:%u}",
-			       data_version, vnode->fid.vid, vnode->fid.vnode);
+			       (unsigned long long) data_version,
+			       vnode->fid.vid, vnode->fid.vnode);
 			set_bit(AFS_VNODE_MODIFIED, &vnode->flags);
 			set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
 		}