From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Date: Fri, 02 Jul 2004 06:18:44 +0000 Subject: Re: [PATCH] IA64 audit support Message-Id: <20040701231844.0aed5201.akpm@osdl.org> List-Id: References: <200406301556.i5UFuGg8009251@redrum.boston.redhat.com> <20040701124644.5e301ca0.akpm@osdl.org> <40E4B20F.8010503@opersys.com> <20040701182954.43351d36.akpm@osdl.org> <40E4D4AD.2020302@opersys.com> In-Reply-To: <40E4D4AD.2020302@opersys.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: karim@opersys.com Cc: peterm@redhat.com, faith@redhat.com, davidm@hpl.hp.com, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, ray.lanza@hp.com, trz@us.ibm.com, richardj_moore@uk.ibm.com, bob@watson.ibm.com, michel.dagenais@polymtl.ca Karim Yaghmour 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/