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    SubjectRe: [PATCH] x86: Don't randomize stack unless current->personality permits it
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    On Sat, 2006-07-15 at 17:09 +0300, Al Boldi wrote:
    > Arjan van de Ven wrote:
    > > On Sat, 2006-07-15 at 14:29 +0300, Al Boldi wrote:
    > > > Arjan van de Ven wrote:
    > > > > > BTW, why does randomize_stack_top() mod against (8192*1024) instead
    > > > > > of (8192) like arch_align_stack()?
    > > > >
    > > > > because it wants to randomize for 8Mb, unlike arch_align_stack which
    > > > > wants to randomize the last 8Kb within this 8Mb ;)
    > > >
    > > > Randomizing twice?
    > >
    > > a VMA can only be randomized in 4Kb (well page size) granularity, so the
    > > 8Mb randomization can only work in that 4Kb unit, the "second"
    > > randomization can work in 16 byte granularity.
    > >
    > > > There is even a case where a mere rename or running through an extra
    > > > shell causes a slowdown. And that's with randomization turned off.
    > >
    > > randomization off will slow stuff down yes... you get cache alias
    > > contention that way.

    a question.. do you have prelink installed/active on your system? that
    may very well mess with timings...

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