ERROR::PASS2

Section: Misc. Reference Manual Pages (7stap)
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NAME

error::pass2 - systemtap pass-2 errors

Errors that occur during pass 2 (elaboration) can have a variety of causes. Common types include:

unavailable probe points: Some types of probe points are only available on certain system versions, architectures, and configurations. For example, user-space (process.) probes may require utrace or uprobes capability in the kernel for this architecture. Debugging or symbol data may be absent for .function or .statement probes. Use the stap -L option to list available probe points. Use the ! or ? probe point suffixes to denote optional / preferred-alternatives, to let the working parts of a script continue. Check for availability of debuginfo.
typos: There might be a spelling error in the probe point name ("sycsall" vs. "syscall"). Wildcard probes may not find a match at all in the tapsets. Recheck the names.
unavailable context variables: Systemtap scripts often wish to refer to variables from the context of the probed programs using $variable notation. These variables may not always be available, depending on versions of the compiler, debugging/optimization flags used, architecture, etc. Use the @defined() expression to test for the resolvability of a context variable expression. Consider using the stap --skip-badvars option to silently replace misbehaving context variable expressions with zero.

Increasing the verbosity of pass-2 with an option such as --vp 02 can help pinpoint the problem.

This document was created by man2html, using the manual pages.
Time: 09:58:21 GMT, March 20, 2013