Messages in this thread | | | From | Will Deacon <> | Subject | Re: [PATCH v2] arm64: Enable data independent timing (DIT) in the kernel | Date | Tue, 8 Nov 2022 17:38:39 +0000 |
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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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