diff --git a/module/zfs/dmu.c b/module/zfs/dmu.c
index 63464d747..909605aa2 100644
--- a/module/zfs/dmu.c
+++ b/module/zfs/dmu.c
@@ -1482,9 +1482,9 @@ dmu_assign_arcbuf_by_dnode(dnode_t *dn, uint64_t offset, arc_buf_t *buf,
 	rw_enter(&dn->dn_struct_rwlock, RW_READER);
 	blkid = dbuf_whichblock(dn, 0, offset);
 	db = dbuf_hold(dn, blkid, FTAG);
+	rw_exit(&dn->dn_struct_rwlock);
 	if (db == NULL)
 		return (SET_ERROR(EIO));
-	rw_exit(&dn->dn_struct_rwlock);
 
 	/*
 	 * We can only assign if the offset is aligned and the arc buf is the