RHEL 7.6: NFS share hangs when NFS operations are in-progress and a network partition occurs involving an unexpected RST

Issue

• After upgrading from the RHEL7.5 kernel (3.10.0-862*el7) to the RHEL7.6 kernel (3.10.0-957*el7), reads or writes to a NFS share by a NFS client hang indefinitely following a network partition and recovery.
• NFS share is hung with a task, such as kworker, consuming 100% of CPU and the /proc/<pid>/stack or other backtrace shows execution in the sunrpc transmit path
• Processes can not be killed and a reboot of the NFS client is required.
• This is new behaviour that is not seen in versions of RHEL 7 prior to RHEL 7.6