This assignment is expected to be completed in an hour. Debugging kernel code for vlan and bridge. Some error is introduced due to patching. It is insane to expect someone to solve this in an hour. Specially if you are not familiar with source code. If issue was due to patching, version control system should be provided to see which patches went in recently. This will help narrow down root cause. But no version control was provided. Interview process is bizarre. This assignment is very time consuming. If you cant find solution in an hour leave it. This company is not worth it!!