diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c
index 1fab37d44029..46b7a1ae9ff2 100644
--- a/sys/kern/vfs_bio.c
+++ b/sys/kern/vfs_bio.c
@@ -1965,6 +1965,7 @@ restart:
 		int flags;
 		char *waitmsg;
 
+		mtx_unlock(&bqlock);
 		if (defrag) {
 			flags = VFS_BIO_NEED_BUFSPACE;
 			waitmsg = "nbufkv";