Re: __ps_strings and compat32

[christos%astron.com@localhost (Christos Zoulas)]

In article <20110104120934.GA30484%britannica.bec.de@localhost>,
Joerg Sonnenberger  <joerg%britannica.bec.de@localhost> wrote:
>Hi all,
>while investigating ways to access the auxillary vector, I found that we
>currently don't deal correctly with struct ps_strings in 32bit compat.
>This structure is placed by the kernel into the initial stack and
>referenced in userland by __ps_strings. It is used by setproctitle(3)
>and therefore e.g. by programs that want to include a status report in
>the ps(1) output. This naturally works only by chance, if at all in
>compat32. How do we want to deal with it?
>
>Variant 1: Leave it as broken. It should be said that having reliable
>ps_strings could speed up ld.elf_so a bit.
>
>Variant 2: Introduce two methods for obtaining and setting ps_strings of
>a specific process and hook those into the normal exec mechanism. This
>would in theory allow emulations pretty arbitrary data structures.
>
>Other options that are better?

Something like a mapped page for each process to store:

        - thread id
        - clock
        - optimized memcpy/memmove/memset for the processor
        - ps_string info

etc. This could be mapped at a known location.


christos