1ERROR::PASS5(7stap)                                        ERROR::PASS5(7stap)
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NAME

6       error::pass5 - systemtap pass-5 errors
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DESCRIPTION

10       Errors  that  occur  during  pass  5  (execution) can have a variety of
11       causes.
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14       exceptional events during script execution
15              The systemtap translator  and  runtime  include  numerous  error
16              checks  that  aim to protect the systems and the users from mis‐
17              takes or transient conditions.  The script may deliberately call
18              the  error()  tapset  function to signal a problem.  Some memory
19              needed for  accessing  $context  variables  may  be  temporarily
20              unavailable.   Consider  using  the  try/catch construct to wrap
21              script fragments in exception-handling code.  Consider using the
22              stap --suppress-handler-errors or stap --skip-badvars option.
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25       resource exhaustion
26              One  of  several  types  of space or time resource limits may be
27              exceeded by the script,  including  system  overload,  too  many
28              tuples  to  be  stored in an array, etc.  Some of the error mes‐
29              sages identify the constraint by macro name, which may be  indi‐
30              vidually  raised.   Consider  using the stap --suppress-handler-
31              errors and/or stap -g --suppress-time-limits options.  Extend or
32              disable    individual    resource    limits   using   the   stap
33              -DSOME_LIMIT=NNNN option.  The stap -t option may identify those
34              probes that are taking too long.
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37       remote execution server problems
38              If you use the stap --remote option to direct a systemtap script
39              to be executed somewhere else, ensure that an SSH connection may
40              be  made to the remote host, and that it has the current system‐
41              tap runtime installed & available.
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44       installation/permission problems
45              It is possible that your copy of  systemtap  was  not  correctly
46              installed.   For  example, the /usr/bin/staprun program may lack
47              the necessary setuid permissions, or your invoking userid  might
48              not  have  sufficient  privileges  (root, or stapusr and related
49              group memberships).  Environment variables  may  interfere  with
50              locating /usr/libexec/.../stapio.
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53       security configuration
54              SecureBoot  or  other module signing machinery may be in effect,
55              preventing .ko module loading.  A local  or  remote  stap-server
56              service would be necessary to securely manage keys.  This situa‐
57              tion is detected automatically on most kernels, but on some, the
58              SYSTEMTAP_SIGN environment varible may have to be set to trigger
59              this extra signing-related processing.
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61              The normal kernel-module based systemtap  backend  may  be  more
62              than  your  script  requires.   Try stap --runtime=bpfand/orstap
63              --runtime=dyninst backends.  Though they have  inherent  limita‐
64              tions, they operate with lesser privileges and perceived risks.
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67       errors from target program
68              The  program  invoked  by the stap -c CMD option may exit with a
69              non-zero code.
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72       uncaught exceptions in the target program
73              When using --runtime=dyninst you may encounter  an  issue  where
74              the  target program aborts with a message like "terminate called
75              after throwing an instance of 'foo_exception'".  This is  unfor‐
76              tunately  a  limitation  of  Dyninst,  which  sometimes prevents
77              exceptions from properly unwinding through instrumented code.
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GATHERING MORE INFORMATION

82       Increasing the verbosity of pass-5 with an option such  as  --vp  00001
83       can help pinpoint the problem.
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SEE ALSO

87       stap(1),
88       http://sourceware.org/systemtap/wiki/TipExhaustedResourceErrors,
89       error::fault(7stap),
90       error::reporting(7stap)
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94                                                           ERROR::PASS5(7stap)
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