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    SubjectRe: Info: mapping multiple BARs. Your kernel is fine.
    On Sat, Mar 15, 2014 at 03:15:04PM +0100, Rafael J. Wysocki wrote:
    > I've just gone throught this.

    Thanks.

    > So the problem is that we have the PNP "system" driver whose only purpose seems
    > to be to reserve system resources so that the PCI layer doesn't assign them to
    > new devices on hotplug (disclaimer: I didn't invent it, I only read the code and
    > comments in there).
    >
    > It does that for ACPI device objects having the "PNP0C02" and "PNP0C01" IDs.

    Right, pnp 00:01 is PNP0C02.

    > Apparently, snb_uncore_imc_init_box() steps on a range already reserved by that
    > driver on your box. And this doesn't seem to be a coincidence, because the ACPI
    > device object in question probably *does* correspond to the memory controller
    > that the uncore driver attempts to use.
    >
    > I'm not sure how to address that right now to be honest. Arguably, the PNP
    > "system" driver should be replaced with something saner, but still the
    > resources it claims need to be kept out of reach of the PCI's resource
    > allocation code.

    Well, I'm only conjecturing here but there should be a way for the
    uncore code to tell the PNP "system" driver to free this resource
    because uncore is going to use it now. Or something to that effect.

    Oh well.


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