Re: [BProc] VMADump with non-exported sys_call_table

[<er...@he...>]

On Mon, Jun 09, 2003 at 06:27:30PM -0700, Paul Hartke wrote:
> Hi all,
> 
> I would like to use VMADump standalone (ie, without the rest of Bproc) 
> to checkpoint longrunning applications.  It currently works fine for 
> that.  However, with the new Linux kernels, the sys_call_table is no 
> longer exported so a new mechanism is needed over what is currently 
> provided in VMADump.  Are folks looking into this already?   If so, I 
> don't want to reinvent the wheel.   Ideally, the solution would not 
> involve end users needing to recompile their kernel but they could 
> simply load a module and be up and running--just as things work now.  

Yeah, something is going to have to be done about that.  I agree that
having to patch the kernel for things like this is disgusting but it
may be the only "clean" option.

If you REALLY don't want to recompile and you're willing to try
something which as best "unclean" and may even be "gross and
disgusting" there's this little gizmo I call "symdm" that I use to
resolve symbol problems when I'm just fooling around with stuff.  It's
a little tool to export arbitrary name/address pairs.

You can download it from:

http://www.acl.lanl.gov/supermon/symdm.html

Matt Sottile also did a nice little write-up for it there.

> From the Linux-Kernel Mail Archive, I see that Erik requested a 
> dedicated syscall number for that.  What is the status of that?

I think the answer was "no".  BProc's syscall API was deemed "badly
designed".  There were some philosophical differences there.  I think
the messages in the archives sum it up pretty well.

Considering BProc's status as a kernel patch, it always requires a
rebuild so it doesn't matter if it's blessed by the keepers of the tar
ball.

- Erik