NAME¶

warning::symbols - systemtap missing-symbols warnings

DESCRIPTION¶

For some probing operations, where DWARF debugging data is not available, systemtap needs ELF symbols for the relevant binaries. This allows at least probe addresses to be calculated, some variables resolved, and with @cast() and headers, maybe even some types.

kernel symbol table

Systemtap may need a linux-build style System.map file to find addresses of kernel functions/data. It may be possible to create it by hand:

% su
# cp /proc/kallsyms /boot/System.map-`uname -r`
or
# nm /lib/modules/`uname -r`/build/vmlinux > /boot/System.map-`uname -r`

minisymbols

On some systems, binaries may be compiled with a subset of symbols useful for function tracing and backtraces. This 'Minisymbols' is a xz compressed section labeled .gnu_debugdata. Support for minisymbols relies on elfutils version 0.156 or later.

compressed symbols

On some systems, symbols may be available, but compressed into .zdebug_* sections. Support for compressed symbols relies on elfutils version 0.153 or later.

SEE ALSO¶

stap(1),
stappaths(7),
strip(1),
warning::debuginfo(7stap),
error::dwarf(7stap),
error::reporting(7stap),
http://fedoraproject.org/wiki/Features/MiniDebugInfo