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Subject: Re: [RFC 09/10] x86/enter: Create macros to restrict/unrestrict
 Indirect Branch Speculation
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On 23/01/2018 10:30, David Woodhouse wrote:

> Skylake takes predictions from the generic branch target buffer when
> the RSB underflows.

Adding LAKML.

AFAIU, some ARM Cortex cores have the same optimization.
(A9 maybe, A17 probably, some recent 64-bit cores)

Are there software work-arounds for Spectre planned for arm32 and arm64?

Regards.