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Date: Fri, 5 Jan 2018 23:43:57 +0100
From: Borislav Petkov <bp@suse.de>
To: "Woodhouse, David" <dwmw@amazon.co.uk>
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Subject: Re: [PATCH v3 01/13] x86/retpoline: Add initial retpoline support
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On Fri, Jan 05, 2018 at 10:16:54PM +0000, Woodhouse, David wrote:
> You'd still want a RETPOLINE_AMD flag to enable that lfence; it's not
> just K8.

I think you're forgetting that we set K8 on everything >= K8 on AMD. So
this:

+       if (c->x86_vendor == X86_VENDOR_AMD)
+               setup_force_cpu_cap(X86_FEATURE_RETPOLINE_AMD);

can just as well be dropped and X86_FEATURE_K8 used everywhere.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--