Author: Julia Lawall <julia@diku.dk> If reply is ERR_PTR(…), then it should not be dereferenced, so I have moved the dereference from the declaration to after the IS_ERR test. The semantic match that finds the problem is as follows: (http://www.emn.fr/x-info/coccinelle/) // @match exists@ expression x, E; identifier fld; position p1,p2; @@ ( x = E; | …