Date: Thu, 2 Jun 2011 09:45:30 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Vince Weaver <vweaver1@eecs.utk.edu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, linux-kernel@vger.kernel.org,
        paulus@samba.org, acme@redhat.com, torvalds@linux-foundation.org
Subject: Re: perf: definition of a "regression"
Message-ID: <20110602074530.GF2150@elte.hu>
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 <alpine.DEB.2.00.1105272332400.9313@cl320.eecs.utk.edu>
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* Vince Weaver <vweaver1@eecs.utk.edu> wrote:

> On Sat, 28 May 2011, Peter Zijlstra wrote:
> 
> > On Fri, 2011-05-27 at 23:38 -0400, Vince Weaver wrote:
> > > on that note (and while trying to document exactly what the ioctls do) it 
> > > seems that a PERF_EVENT_IOC_REFRESH with an argument of anything higher 
> > > than one does not work on kernels 2.6.36 and newer.  The behavior acts
> > > as if 1 was passed, even if you pass in, say, 3.
> > 
> > Urgh, no that should definitely work. Thanks for the test-case, I'll
> > work on that (probably not until Monday though, but who knows).
> 
> So wait, the two regressions I found in 2.6.37 are WONTFIX because 
> they are too old, even though they break existing userspace code?
> 
> And this older regression in 2.6.36 is going to be fixed, even 
> though perf, PAPI, and libpfm4 don't trigger the buggy 
> functionality at all?

Btw., these considerations are flexible and we can reconsider and 
change the WONTFIX if there's a patch available and doesn't look 
horrible to backport. We can also mark fixes that havent been marked 
-stable originally as -stable later on, etc.

So please don't feel needlessly bitter about past decisions: when 
there's some good technical solution to a problem (or we were plain 
out wrong about a decision) we try hard not to stand in the way.

Thanks,

	Ingo
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