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Date: Wed, 10 Jan 2018 02:50:12 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Andi Kleen <andi@firstfloor.org>
cc: Tom Lendacky <thomas.lendacky@amd.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        Dave Hansen <dave.hansen@intel.com>,
        Jiri Kosina <jikos@kernel.org>, Andi Kleen <ak@linux.intel.com>
Subject: Re: [PATCH] x86/retpoline: Fix NOSPEC_JMP for tip
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On Tue, 9 Jan 2018, Andi Kleen wrote:

> > > I think there are areas that rely on X86_FEATURE_RETPOLINE being set
> > > even if X86_FEATURE_RETPOLINE_AMD is set.  For example, line 261 in
> > > arch/x86/entry/entry_32.S is only checking for X86_FEATURE_RETPOLINE.
> > 
> > I audited the difference places. They all seem ok.
> 
> Actually 32bit is not ok. For 32bit we need COMMON. So adding it.

Please keep the current X86_FEATURE_RETPOLINE as the common one and add a
new X86_FEATURE_RETPOLINE_GENERIC which is selected by the generic/intel
side. Little more churn, but clearer.

Thanks,

	tglx