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    SubjectRe: [PATCH v2] arm64: Enable data independent timing (DIT) in the kernel
    Date
    On Mon, 7 Nov 2022 18:24:00 +0100, Ard Biesheuvel wrote:
    > The ARM architecture revision v8.4 introduces a data independent timing
    > control (DIT) which can be set at any exception level, and instructs the
    > CPU to avoid optimizations that may result in a correlation between the
    > execution time of certain instructions and the value of the data they
    > operate on.
    >
    > The DIT bit is part of PSTATE, and is therefore context switched as
    > usual, given that it becomes part of the saved program state (SPSR) when
    > taking an exception. We have also defined a hwcap for DIT, and so user
    > space can discover already whether or nor DIT is available. This means
    > that, as far as user space is concerned, DIT is wired up and fully
    > functional.
    >
    > [...]

    Applied to arm64 (for-next/cpufeature), thanks!

    [1/1] arm64: Enable data independent timing (DIT) in the kernel
    https://git.kernel.org/arm64/c/01ab991fc0ee

    Cheers,
    --
    Will

    https://fixes.arm64.dev
    https://next.arm64.dev
    https://will.arm64.dev

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