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    SubjectRe: 2.2.0pre1 OOPS on boot.
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    Linus Torvalds wrote:
    > It probably _also_ makes sense to make the optimizations a bit more
    > specific, so that we'd have:
    >
    > - completely generic (rather than calling it "386" - just say that it
    > is supposed to works on every ia32 machine)
    > - 486-specific: the current i486, with the ridiculous alignments that
    > that entails. Not recommended for _anything_ else than a i486.
    > - i486+: the old "Pentium" - works on i486 machines, but without the
    > stupid alignment, so it is smaller and faster on Pentium class machines
    > too. Doesn't require a TSC, so it works on pseudo-pentiums too. This is
    > apparently what you thought was "generic".
    > - Pentium+: requires TSC
    > - PentiumPro: requires TSC, conditional move instructions, and a fixed
    > local APIC for SMP.
    >
    > Would that kind of split work for you? We could also make it _really_
    > specific.

    Linus,

    wouldn't it be better to do something like

    config_486_alignment (does the "rediculous alingments" for '486)
    config_assume_working_tsc (you call that pentium+)
    config_assume_working_apic (pentium pro)

    That way if you turn on "assume working tsc" you'll get a kernel
    that does that assumption, possibly augmented with:

    panic ("Your machine doesn't have a working tsc, "
    "but this kernel was built with that assumption");

    (just like for the math coprocessor stuff.)

    Of these options, the first is an performance issue: 486s will run
    faster, others will not notice/ perform slightly worse. The others
    statically compile assumptions into the kernel, which if not true
    prevents the kernel from running.....

    Why change it now? Well, this way we can expand towards the future
    where every different processor has specific features. That way we
    lose the intel-names that may or may not apply to intel-competitors.


    Roger.

    --
    ** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2137555 **
    *-- BitWizard writes Linux device drivers for any device you may have! --*
    * Never blow in a cat's ear because if you do, usually after three or *
    * four times, they will bite your lips! And they don't let go for at *
    * least a minute. -- Lisa Coburn, age 9

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