error::fault - memory access faults
Read or write faults can occur during the operation of a systemtap script, if the script causes dereferencing of a pointer that turns out to be invalid. This can be caused by using context variables that do not happen to have valid values, or perhaps references to memory that is unavailable at that moment due to paging. These fault conditions are benign because they are caught by the systemtap runtime, which cleanly terminates the script. If quick termination is not desired, consider using the --skip-badvars or --suppress-handler-errors or -DMAXERRORS=NN stap options, or wrapping relevant parts of the probe handlers in a try/catch block. It may be possible to adjust the target program, to make it more likely that needed context variables are paged in when systemtap looks for them. Consider adding some lightweight processing on the key variables, like a strlen(foo) for a string, or iterating across elements of an array or linked list, or touching a few bytes of a heap-allocated block. The idea is to trigger any page faults in the target program, before systemtap would need to (but can't).
This page is part of the systemtap (a tracing and live-system analysis tool) project. Information about the project can be found at ⟨https://sourceware.org/systemtap/⟩. If you have a bug report for this manual page, send it to firstname.lastname@example.org. This page was obtained from the project's upstream Git repository ⟨git://sourceware.org/git/systemtap.git⟩ on 2017-04-25. If you dis‐ cover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to email@example.com ERROR::FAULT(7stap)
Pages that refer to this page: stapprobes(3stap), error::pass5(7stap)