The attached patch fixes the SEGV and lets GDB successfully
load all kernel modules installed by default on RHEL 7. GDB
still aborts when attempting to list functions in many of
the modules but that's a separate problem (bug #17993).

The patch has been tested on ppc64 with the results below.

		=== gdb Summary ===

                               PATCHED   unpatched
# of expected passes            29991       29989
# of unexpected failures        103         103
# of unexpected successes       1           1
# of expected failures          67          67
# of known failures             54          54
# of untested testcases         32          32
# of unsupported tests          190         190

Martin