[CentOS] Firefox and Thunderbird freeze/crash followed by "nfs4_reclaim_open_state: Lock reclaim failed!" syslog messages

Wed Jun 6 15:26:23 UTC 2018
Frank Thommen <list.centos at drosera.ch>


since I updated my workstation from CentOS 7.4 to 7.5, Firefox and 
Thunderbird (both 52.8.0, from CentOS repos) regularly freeze (or crash) 
and cannot be restarted afterwards.  Trying to start them results in a 
"Bus error (core dumped)" (Firefox) and "Killed" (Thunderbird).  The 
system log then shows:

      kernel: NFS: nfs4_reclaim_open_state: Lock reclaim failed!

each time I try to start the applications (our homedirectories are 
mounted via NFS4).  As far as I can see, no other applications are 
affected.  The workstation needs to be rebooted to fix the situation.

Has anyone else seen that or knows how to debug or fix this issue? I 
tried with strace and wireshark w/o finding anything helpful.