Messages in this thread | | | Date | Thu, 29 Nov 2018 18:15:39 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH v2 4/4] x86/static_call: Add inline static call implementation for x86-64 |
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On Thu, Nov 29, 2018 at 08:59:31AM -0800, Andy Lutomirski wrote:
> If you make it conditional on CPL, do it for 32-bit as well, add > comments,
> and convince yourself that there isn’t a better solution > (like pointing IP at a stub that retpolines to the target by reading > the function pointer, a la the unoptimizable version), then okay, I > guess, with only a small amount of grumbling.
Right; so we _could_ grow the trampoline with a retpoline indirect call and ret. It just makes the trampoline a whole lot bigger, but it could work.
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