Because you are using a serial link you certainly want to close any
related to extra data you don't need. Not knowing a whole lot about
what the Eclipse plugin gdb does, it is hard to know if this was an
eclipse timeout or not.
If you add the following to your .gdbinit it will at least tell you what
happened at the end.
set remotelogfile /tmp/gdb_serial_log.txt
It would be good to know if eclipse timed out and it just detached from
the target, or if some command crashed gdb. It is purely a guess, but
it is probably eclipse requesting lots of information and simply timing out.
The "junk" you speak of is simply the gdb serial traffic, it is answered
in the FAQ
I would not expect the terminal session to crash. If an oops is
printed, it means there is an internal kgdb problem.