Re: [RFC 0/2] __vdso_findsym

H. Peter Anvin
2014-06-15T17:06:00Z

On 06/15/2014 07:35 AM, Rich Felker wrote:
>
> Arguably, it was a mistake for the kernel to expose a virtual ELF to
> begin with, and it should just have exposed a "lookup function by
> name" operation to begin with. Yes this can be done in userspace, but
> I see it more as a matter of "fixing a broken API design".
>

What the fsck are you smoking? There is immense value in providing a
stable and very well-defined data structure, which also happens to be
what dynamic linkers already want to consume. Providing a helper for
crippled libc applications has potential value. Shaving a few hundred
bytes off static applications is a very weak argument, simply because it
is such a small fraction of the enormous cost of a static application,
and static applications are problematic in a number of other ways,
especially the lack of ability to fix bugs.

Treating the kernel as an ersatz dynamic library for "static"
applications is kind of silly -- after all, why not provide an entire
libc in the vdso? I have actually seen people advocate for doing that.

-hpa