[arch-general] strange behaviour after 3.18.6 kernel update

[Genes Lists]

   I have one server which does  internal mail and nfs - which went 
weird after about a day on the new kernel.

   I remote admin via ssh - symptom on the terminal was many commands 
failed in bad ways. Though 'ls' seemed to be fine.

    e.g. vi - gave input/output error.
         journalctl -lf -> bus error

     Rebooted and it hung on shutdown - there were manu input/output 
errors on the console - after it stopped on systemd shutdown target and 
got no further - i hard powered off and back on.

   Machine came up fine - journalct shows all logging stopped at 9.14 pm 
and resumed as normal after the reboot at 10.30 pm.

   Any advice as to what to look for? Anyone else seeing strange IO 
errors after a period?

thanks.

gene