lkml.org 
[lkml]   [2007]   [Feb]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 0/4] coredump: core dump masking support v3
Kawai, Hidehiro wrote:
> This patch series is version 3 of the core dump masking feature,
> which provides a per-process flag not to dump anonymous shared
> memory segments.

I just wanted to remind you that you need to be careful about dumping
the [vdso] segment no matter whether you omit other segments. I didn't
actually try running your patches, and if the kernel doesn't actually
consider this segment anonymous and shared, things might already work
fine as is.

In any case, you can check with "readelf -a", if the [vdso] segment is
there. And you will find that if you forget to dump it, "gdb" can no
longer give you stack traces on call chains that involve signal handlers.

As an alternative to your kernel patch, you could achieve the same goal
in user space, by linking my coredumper
http://code.google.com/p/google-coredumper/ into your binaries and
setting up appropriate signal handlers. An equivalent patch for
selectively omitting memory regions would be trivial to add. While this
does give you more flexibility, it of course has the drawback of
requiring you to change your applications, so there still is some
benefit in a kernelspace solution.


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

\
 
 \ /
  Last update: 2007-02-24 04:35    [from the cache]
©2003-2011 Jasper Spaans