The rte_hash_lookup_data function has the potential to return a ZERO value, contrary to what the description indicates. The description specifies that "A positive value that can be used by the caller as an offset into an array of user data". To address this issue, I submitted a patch, which can be found at: http://patches.dpdk.org/project/dpdk/patch/1656335481-238112-1-git-send-email-ccm@ccm.ink/