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    SubjectRe: [PATCH v5 1/4] riscv: Move kernel mapping to vmalloc zone
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    On Thu, 2020-07-23 at 01:21 -0400, Alex Ghiti wrote:
    > > works fine with huge pages, what is your problem there ? You rely on
    > > punching small-page size holes in there ?
    > >
    >
    > ARCH_HAS_STRICT_KERNEL_RWX prevents the use of a hugepage for the kernel
    > mapping in the direct mapping as it sets different permissions to
    > different part of the kernel (data, text..etc).

    Ah ok, that can be solved in a couple of ways...

    One is to use the linker script to ensure those sections are linked
    HUGE_PAGE_SIZE appart and moved appropriately by early boot code. One
    is to selectively degrade just those huge pages.

    I'm not familiar with the RiscV MMU (I should probably go have a look)
    but if it's a classic radix tree with huge pages at PUD/PMD level, then
    you could just degrade the one(s) that cross those boundaries.

    Cheers,
    Ben.


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