Accessing shared memory

Accessing shared memory

[K. Jagielski]

Hello,
I'm allocating a memory block inside a kernel module and then I share
it with an user space application through mmap(). I have two problems:
1. The memory isn't written into core files
2. The memory isn't accessible during "runtime" debugging (the result
of "attach" command & similar)

How to solve those issues?

Regards,
Krzysztof

Re: Accessing shared memory

[Ine Ya]

Hi,

for coredumps:
check /proc/<pid>/maps and find out what flags this area has.
Then you can try to change the flags, so vma_dump_size() would not
return 0, or change this function for your needs and rebuild the
kernel.
http://lxr.linux.no/#linux+v2.6.32/fs/binfmt_elf.c#L1150

Hope this helps (I haven't tried this before),
Ineya

On Thu, Feb 18, 2010 at 4:04 PM, K. Jagielski <gilvannco@gmail.com> wrote:
> Hello,
> I'm allocating a memory block inside a kernel module and then I share
> it with an user space application through mmap(). I have two problems:
> 1. The memory isn't written into core files
> 2. The memory isn't accessible during "runtime" debugging (the result
> of "attach" command & similar)
>
> How to solve those issues?
>
> Regards,
> Krzysztof
>