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    SubjectRe: kmalloc
    Hi Gerard,

    > I didn't write that I didn't want MMIO regions to be memory-mapped from
    > user space, nor I forget this need, and I will probably _never_ write
    > that. It is its memory-like based design that makes PCI so simple and
    > pleasant. I already wrote about what I think about hardwares that do not
    > have a unified memory addressing for all BUSES and host memory that break
    > the simplicity of PCI and introduced the complexity with addressing we
    > have to deal with.

    I share the same opinion, but since most PCI cards support only
    32-bit addressing and we certainly want to support both PCI and >4G
    of memory on 64-bit architectures, we probably need to extend
    the interface a bit to cover IOMMU-like translation as well as
    pure all-in-the-same-space cases.

    > I was only speaking about the base_addresses provided by the pci_dev
    > structure that has been presented as some input parameters for ioremap()
    > and told that this is _not_, in my opinion, what a PCI device driver
    > expects as kernel service, or at least _not_ enough.

    This is certainly not enough and I it's probably my fault my explanation
    sounded like "these are just ioremap() cookies" -- I meant to say that
    these are physical addresses, suitable for example for ioremap()
    or mmap() on /dev/mem.

    Have a nice fortnight
    --
    Martin `MJ' Mares <mj@ucw.cz> http://atrey.karlin.mff.cuni.cz/~mj/
    Faculty of Math and Physics, Charles University, Prague, Czech Rep., Earth
    "DEC = Delay in Error Correction"

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