Re: [PATCH v3 3/3] x86/retpoline: Convert generic specific retpolines to use RETPOLINE_GENERIC

[Tom Lendacky]

On 1/10/2018 7:15 AM, Woodhouse, David wrote:
> On Tue, 2018-01-09 at 18:28 -0800, Andi Kleen wrote:
>> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
>>
>> X86_FEATURE_RETPOLINE has been renamed to X86_FEATURE_RETPOLINE_GENERIC.
>> Convert the sequences using it.
> 
> AMD documentation says they need the RSB fill too, so these should stay
> under X86_FEATURE_RETPOLINE I think.

AMD processors don't fall back to the indirect predictor on an underflow
so this isn't needed on AMD if it is purely for underflow prevention.

Thanks,
Tom

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