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    SubjectRe: New resources - pls, explain :-(
    > (I exaggerate.  Alan Cox said that not reordering was a safer default
    > (which is essentially my position) and Dave Miller said to me in
    > private email something along the lines that any sane architecture has
    > a side-effect bit in the PTEs to prevent reordering of accesses to
    > certain pages.)

    How many insane architectures are there in the world though.

    > this: ncr, aic7xxx, tulip, epic100. How many others would there be in
    > this category? It sounds to me like the vast majority of drivers
    > which use readl/writel would be assuming that they prevent reordering.

    I think that is fairly accurate.

    > My position is that readl/writel should prevent reordering (of the
    > accesses generated by read*/write*), and that we should have variants,
    > maybe called readl_fast etc., for the cases where performance is
    > crucial and the driver writer is willing to put in explicit barriers
    > where necessary.


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