Re: Adding(?) XI support to MIPS-Linux?

[Thiemo Seufer <ths@networkno.de>]

Kevin D. Kissell wrote:
[snip]
>>  Broadly, what I'm trying to say is I don't want to touch gcc
>>  (and/or binutils) and am unconvinced I have to.  But I'm very
>>  much open to correction here!
>>
>>  The x86 (including amd64) and, AFAIK, SuperH (sh) Linux kernels
>>  now support NX or equivalent; indeed, a test on my 2.6.22(-ish)
>>  amd64 workstation (Kubuntu 7.10) has a non-executable stack.
>>  As such, those could be a model worth studying/following, but
>>  I understand they have support for specially-marked binaries to
>>  have executable stacks (i.e., binutils/gcc mods, which I want to
>>  avoid).
> Well, strictly speaking, you wouldn't actually *need* to modify binutils
> to make specially tagged binaries.  You could borrow an unused bit in
> the ELF header somewhere, have the kernel recognize it, and write your
> own little tool that only turns that bit on/off in an ELF file.

This exists already in ld's -z execstack/noexecstack feature. It is
not used by default because too many things depend on executable
stacks on MIPS.


Thiemo