Re: [PATCH] IA64 audit support

[Andrew Morton <akpm@osdl.org>]

Karim Yaghmour <karim@opersys.com> wrote:
>
> > Developer support tools are good, but are not as persuasive as end-user
> > features.  Because the audience is smaller, and developers know how to
> > apply patches and rebuild stuff.
> 
> This is probably one of the biggest misconception about LTT amongst kernel
> developers. So let me present this once more: LTT is _NOT_ for kernel
> developers, it has never been developed with this crowd in mind. LTT is and
> has _ALWAYS_ been intended for the end user.

Note I said "developer", not "kernel developer".  If the audience for a
feature is kernel developers, userspace developers and perhaps the most
sophisticated sysadmins then that's a small audience.  It's certainly an
_important_ audience, but the feature is not as important as those
codepaths which Uncle Tillie needs to run his applications.

> Again, LTT is of marginal use to kernel developers, the benefits all go
> to the end users' ability to understand what's going on in their system (see
> above for examples.)

To me, an "end user" is one who is capable of identifying the power switch
and the ANY key, not an application programmer!

> On the topic of maintenance cost, I fail to see how one-liners such as the
> above can be of any burden to any kernel developer, they have remained
> virtually unchanged for the past 5 years and any look throughout the LTT
> archives or the kernel mailing list archive for LTT patches will readily
> show this.

Fair enough.

> > If it could use kprobes hooks that'd be neat.  kprobes is low-impact.
> 
> The issues about the spread of trace points across the source code are
> exactly the same, you still need to mark the code-paths (and maintain
> these markings for each version) regardless of the mechanism being used.

Nope, kprobes allows a kernel module to patch hooks into the running
binary.  That's all it does, really.   See
http://www-124.ibm.com/linux/projects/kprobes/