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    [W:0.019 / U:75.976 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site