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    SubjectRe: [PATCH v6 11/41] mm: Introduce pte_mkwrite_kernel()
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    On 18.02.23 22:14, Rick Edgecombe wrote:
    > The x86 Control-flow Enforcement Technology (CET) feature includes a new
    > type of memory called shadow stack. This shadow stack memory has some
    > unusual properties, which requires some core mm changes to function
    > properly.
    >
    > One of these changes is to allow for pte_mkwrite() to create different
    > types of writable memory (the existing conventionally writable type and
    > also the new shadow stack type). Future patches will convert pte_mkwrite()
    > to take a VMA in order to facilitate this, however there are places in the
    > kernel where pte_mkwrite() is called outside of the context of a VMA.
    > These are for kernel memory. So create a new variant called
    > pte_mkwrite_kernel() and switch the kernel users over to it. Have
    > pte_mkwrite() and pte_mkwrite_kernel() be the same for now. Future patches
    > will introduce changes to make pte_mkwrite() take a VMA.
    >
    > Only do this for architectures that need it because they call pte_mkwrite()
    > in arch code without an associated VMA. Since it will only currently be
    > used in arch code, so do not include it in arch_pgtable_helpers.rst.
    >
    > Cc: linux-doc@vger.kernel.org
    > Cc: linux-arm-kernel@lists.infradead.org
    > Cc: linux-s390@vger.kernel.org
    > Cc: xen-devel@lists.xenproject.org
    > Cc: linux-arch@vger.kernel.org
    > Cc: linux-mm@kvack.org
    > Tested-by: Pengfei Xu <pengfei.xu@intel.com>
    > Suggested-by: David Hildenbrand <david@redhat.com>
    > Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
    >

    Acked-by: David Hildenbrand <david@redhat.com>

    Do we also have to care about pmd_mkwrite() ?

    --
    Thanks,

    David / dhildenb

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