New module loader makes kernel debugging much harder

From: Keith Owens (kaos@ocs.com.au)
Date: Fri Nov 22 2002 - 21:20:10 EST


The new module loader makes kernel debugging much harder.

There is no section information available, which means ...

* ksymoops cannot decode oops in modules. Without section data, there
  is no way to reliably determine where module symbols were loaded.

* kgdb cannot debug modules. gdb needs to know which modules are
  loaded and where each section of each module starts.

* kdb cannot display the section for a symbol. Which means the user
  cannot do
    objdump -j <section_name> --adjust-vma=<start_address> module
  to map the code to the original object and source.

The complete lack of kernel and module symbols (no /proc/ksyms) means
that ksymoops is now useless on 2.5 kernels. If you get an oops in a
kernel built without kksymoops, there is no way to decode the oops.

Big step backwards, Rusty.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Sat Nov 23 2002 - 22:00:42 EST