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    SubjectRe: [patch] x86, voyager: fix ioremap_nocache()
    Jeff Garzik wrote:
    >
    > Isn't there Yet More Breakage in lib/iomap.c, given these new semantics?
    >
    > if (flags & IORESOURCE_MEM) {
    > if (flags & IORESOURCE_CACHEABLE)
    > return ioremap(start, len);
    > return ioremap_nocache(start, len);
    > }
    >
    > Any driver using pci_iomap() (libata, and others) is affected.
    >
    > I disagree with this semantics change. A number of code places _and
    > drivers_ GET IT RIGHT, and these are all broken now?
    >

    They don't, though. They rely on the MTRRs to get it right for them,
    and the MTRRs will say "uncached" in nearly all cases.

    Consider the case above: you would have gotten the same result
    *regardless*, because the MTRRs would not have made the memory
    cacheable. Yes, it's broken, but it was broken before as well.

    -hpa


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