1.3. Limitations of SystemTap
The current iteration of SystemTap allows for a multitude of
options when probing kernel-space events for a wide range of kernels.
However, SystemTap's ability to probe user-space events depends
on kernel support (the Utrace mechanism) that is not available in many kernels.
As a consequence, only some kernel versions support user-space probing.
At present, the developmental efforts of the SystemTap community
are geared towards improving SystemTap's user-space probing
capabilities.