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    SubjectRe: disabling group leader perf_event
      On 09/06/2010 06:47 PM, Ingo Molnar wrote:
    >> The actual language doesn't really matter.
    > There are 3 basic categories:
    > 1- Most (least abstract) specific code: a block of bytecode in the form
    > of a simplified, executable, kernel-checked x86 machine code block -
    > this is also the fastest form. [yes, this is actually possible.]

    Do you then recompile it? x86 is quite unpleasant.

    > 2- Least specific (most abstract) code: A subset/sideset of C - as it's
    > the most kernel-developer-trustable/debuggable form.
    > 3- Everything else little more than a dot on the spectrum between the
    > first two points.
    > I lean towards #2 - but #1 looks interesting too. #3 is distinctly
    > uninteresting as it cannot be as fast as #1 and cannot be as convenient
    > as #2.

    Curious - how do you guarantee safety of #1 or even #2? Can you point
    me to any research?

    Everything I'm aware of is bytecode with explicit measures to prevent
    forged pointers, but I admit I've spent no time on it. It's interesting
    stuff, though.

    I have a truly marvellous patch that fixes the bug which this
    signature is too narrow to contain.

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      Last update: 2010-09-06 19:59    [W:0.028 / U:30.608 seconds]
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