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Date: Mon, 7 Nov 2011 15:35:14 -0500
From: "Ted Ts'o" <tytso@mit.edu>
To: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: "Frank Ch. Eigler" <fche@redhat.com>, Ingo Molnar <mingo@elte.hu>,
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Subject: Re: [Qemu-devel] [PATCH] KVM: Add wrapper script around QEMU to
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On Mon, Nov 07, 2011 at 10:09:34PM +0200, Pekka Enberg wrote:
> 
> I guess for perf ABI, "perf test" is the closest thing to a
> specification so if your application is using something that's not
> covered by it, you might be in trouble.

I don't believe there's ever been any guarantee that "perf test" from
version N of the kernel will always work on a version N+M of the
kernel.  Perhaps I am wrong, though. If that is a guarantee that the
perf developers are willing to stand behind, or have already made, I
would love to be corrected and would be delighted to hear that in fact
there is a stable, backwards compatible perf ABI.

Regards,

						- Ted