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    SubjectRe: [PATCH v5 00/15] x86: Add support for Clang CFI
    On Wed, Oct 27, 2021 at 02:22:27PM +0200, Ard Biesheuvel wrote:
    > On Wed, 27 Oct 2021 at 14:05, Mark Rutland <mark.rutland@arm.com> wrote:

    > > > Should not this jump-table thingy get converted to an actual function
    > > > address somewhere around arch_static_call_transform() ? This also seems
    > > > relevant for arm64 (which already has CLANG_CFI supported) given:
    > > >
    > > > https://lkml.kernel.org/r/20211025122102.46089-3-frederic@kernel.org
    > >
    > > Ugh, yeah, we'll need to do the function_nocfi() dance somewhere...
    > >
    >
    > Sadly, that only works on symbol names, so we cannot use it to strip
    > CFI-ness from void *func arguments passed into the static call API,
    > unfortunately.

    Right, and while mostly static_call_update() is used, whcih is a macro
    and could possibly be used to wrap this, we very much rely on
    __static_call_update() also working without that wrapper and then we're
    up a creek without no paddles.

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