Re: clone, mm->count, and coredumps

Peter Desnoyers (pjd@fred001.dynip.com)
Thu, 29 Jul 1999 08:49:09 -0400 (EDT)

Brian Kelly wrote:
>
> Ramakrishna@canine.wipinfo.soft.net wrote:
> >Since all the threads ( processes in Linux, though cloned and sharing same
> >MM ) might be running at the time of core-dump in one of the threads,
> >there is most likely possibility of the MM getting changed by the time
> >the dump file is written. This is so because the other processes do not
> >have any knowledge of one of the threads( cloned processes ) being dumped.
>
> True, but I have yet to encounter a threaded core dump where this has
> thrown me off the scent of the real bug.

I'll second that. I tend to be most interested in the stack trace of the
offending thread. Besides, if the thread crashed while it was modifying
global structures that get modified by other threads, it was probably
holding a mutex for those structures while the coredump was being
generated.

I'll send my workaround to Xavier Leroy for inclusion in FAQ.threads,
which currently has some comments about how coredumps don't work with
pthreads.

-- 
............................................................................
 Peter Desnoyers 
 162 Pleasant St.         (617) 661-1979          pjd@fred.cambridge.ma.us
 Cambridge, Mass. 02139   (978) 461-0402 (work)   pjd@giga-net.com 


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