PSARC/2007/509 elfedit

[James Carlson]

Ali Bahrami writes:
> I agree that there is not much value to the end user in setting
> LD_NOEXEC_64 for elfedit. However, someone writing an elfedit module might
> need to force the 32-bit version of their code to run for testing reasons.
> The ability to let the user do that is one reason not to use /usr/lib/isaexec,

Actually, that's not a reason.

If you're using the /usr/lib/isaexec trick, you don't need
LD_NOEXEC_64 at all.  The user can invoke /usr/bin/elfedit if he wants
the system to choose, and can directly invoke /usr/bin/$ISA/elfedit
if he wants to specify 32- or 64-bit operation exactly.

> while following the "linker herd" is the other.

That seems like the main reason.

> The performance impact should be minimal --- the call to isaexec happens
> before the 32-bit elfedit does any work beyond argument processing, so
> the difference between what elfedit and /usr/lib/isaexec do is small.
> 
> I just used cscope to find out who uses conv_check_native:
> 
>      crle, dump, elfdump, ld, mcs/strip, moe, nm, pvs
> 
> It's a larger club than just elfdump.

It wasn't a performance issue, but rather "another one of those
things" issue.

That said, I give.  As long as you're comfortable in that crowd, I
won't complain.

-- 
James Carlson, Solaris Networking              <james.d.carlson at sun.com>
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