Re: linux-next: add utrace tree

Ananth N Mavinakayanahalli
2010-01-29T07:55:38Z

On Fri, Jan 29, 2010 at 01:22:40PM +0530, Ananth N Mavinakayanahalli wrote:
> On Fri, Jan 29, 2010 at 08:39:07AM +0100, Ingo Molnar wrote:
>
> ...
>
> > When we merged kprobes ~10 years ago we made the (rather bad) mistake of
> > merging a raw, opaque facility and leaving 'the rest' up to some other entity.
> > IBM kprobes hackers vanished the day the original kprobes code went upstream
> > and the high level entity never truly materialized in-kernel, for nearly a
> > decade!
>
> I don't know what you are referring to here... Kprobes was merged in
> 2.6.9 (~August 2004 -- less than 6 years ago). Since then, we did work
> on ports to powerpc and s390. We implemented kretprobes. We made it much
> scalable using RCU; we did the powerpc booster to skip single-step when
> possible, not to mention various bug fixes over the years.
>
> Yes, we did not do the perf integration, but perf did not exist then, either.
>
> Its simply wrong to say people 'vanished'.

Oh, and the x86 instruction decoder was initially implemented by us.
Masami has done a great job making it more complete.

Ananth