Re: gdb on Linux Kernel dumps (gdb-kdump)

[Andreas Arnez <arnez@linux.vnet.ibm.com>]

On Thu, Sep 17 2015, Ales Novak wrote:

> Hello,
>
> as was discussed at Andreas Arnez's talk during the GNU Cauldron 2015,
> it would be nice to be able to work with Linux kernel dumps using the
> ordinary gdb.

Agreed ;-)

> [...]
> 
> The gdb-kdump should be considered rather as a proof of concept, yet it
> shows that enabling the kdumps in gdb should be principally easy. It is
> able to open the x86_64 and s390x kdumps. I'd imagine that most of the
> commands of the crash-utility could be reimplemented using the gdb's
> Python interface.

Right.  As pointed out in the talk at the Cauldron, there are already a
few examples in the Linux kernel source tree under "scripts/gdb".  In
addition, this post mentions another GDB-enhancing project for Linux
kernel debugging, named "LKD":

  https://sourceware.org/ml/gdb-patches/2015-06/msg00040.html

The LKD project focuses more on live debugging and thus might be a
useful complement to gdb-kdump.

>
> The example session looks like that:
>
> [...]

Very nice!

> We'd be thankful for any comments!

IMHO, it would be very useful if GDB had support for various Linux
kernel dump formats and for the Linux kernel runtime.  It seems that
gdb-kdump covers both to some extent.

So, how to continue?  Would you be able to convert gdb-kdump into
patches against upstream GDB and send those to the gdb-patches mailing
list?

--
Andreas