After updating the kernel to 3.12.53-40-default samba is no longer
running smoothly. The smbd process often stands at 100% CPU and can not
be removed by kill. From time to time am message like this appears:
BUG: Soft lockup CPU#0 stuck for 22s smbd-notifyd
A server restart is possible and fixes the problem for a while. Using an
older kernel resolves the problem permanently.
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