kernel DSO

[Richard Henderson]

On Tue, Sep 14, 2004 at 09:03:28AM +0200, Jakub Jelinek wrote:
> One is symbol versioning, glibc suddenly looses control of the symbol
> versions which the vDSO is overriding, so coming up with a new symbol
> version for one of these functions is hard.

One possibility here is the symbol forwarding that Sun invented
recently.  You'd have the version symbol in libc, and the forward
would point to the VDSO.  Which adds a tiny bit of extra lookup
during symbol resolution, but no extra overhead when actually 
using the symbol.

> The other is that it badly clashes with prelinking.

Yes, well...  The only solution here is to force conflicts for
symbols in the VDSO.  I would support adding this as a feature for
prelink, so that ppc folk could experiment and see if the tradeoff
is worth it.


r~