TCP checksum offloading not validating all packets on Broadcom NICs

Solution Unverified - Updated -

Issue

Client application experiencing high iowait for NFS traffic.

Reproducing the issue with heavy load and network tracing showed that some WRITE attempts were never being received by the NFS server, but were never sending a confirmation back to the clients.

NFS debug showed that  svc_udp_recvfrom was returning 0, indicating an error, which can occur when it  fails to verify the checksum while copying data from skbuffs into xdr

Environment

Red Hat Enterprise Linux 5 (NFS server)
Red Hat Enterprise Linux 5 (NFS client)

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase of over 48,000 articles and solutions.

Current Customers and Partners

Log in for full access

Log In