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    SubjectRe: [PATCH] x86/PCI: never allocate PCI MMIO resources below BIOS_END
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    I don't think it's sufficient, actually.  We regularly see machines where devices point into e820_reserved memory above 1 MB - because it's a platform device or because firmware (e.g. smm) is touching the device.  I think Bjorn's fix is great for .34, but longer term I think we need to structure the code to actually handle reserved regions differently from occupied/forbidden regions.

    "Jesse Barnes" <jbarnes@virtuousgeek.org> wrote:

    >On Mon, 26 Apr 2010 14:44:50 -0700
    >"H. Peter Anvin" <hpa@zytor.com> wrote:
    >
    >> >
    >> > Agreed. The trickier part is handling any platform devices that
    >> > request_resource against that space. But maybe we don't need to do
    >> > anything special; just making sure we avoid it in the PCI "BIOS" code
    >> > as Bjorn did may be sufficient.
    >> >
    >>
    >> Why is that hard? If a platform device does a request_resource against
    >> that space, it's a request for specific address space and it should be
    >> granted.
    >
    >I was thinking if we made it a special resource type we'd have to
    >change any platform drivers to use it; i.e. it wouldn't be
    >IORESOURCE_MEM or IORESOURCE_IO but IORESOURCE_DRAGONS. That way it
    >wouldn't be part of the normal resource space.
    >
    >But that's definitely overkill. I think Bjorn's fix is sufficient.
    >
    >--
    >Jesse Barnes, Intel Open Source Technology Center

    --
    Sent from my Android phone with K-9 Mail. Please excuse my brevity.
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