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Message-ID: <1516732614.5438.0.camel@linux.intel.com>
Subject: Re: [PATCH] x86/retpoline/entry: Disable the entire SYSCALL64 fast
 path with retpolines on
From: Alan Cox <alan@linux.intel.com>
To: Linus Torvalds <torvalds@linux-foundation.org>, Andy Lutomirski
	 <luto@kernel.org>
Cc: the arch/x86 maintainers <x86@kernel.org>, LKML
 <linux-kernel@vger.kernel.org>, Greg Kroah-Hartman
 <gregkh@linuxfoundation.org>,  Jann Horn <jannh@google.com>, Samuel Neves
 <samuel.c.p.neves@gmail.com>, Dan Williams <dan.j.williams@intel.com>,
 Kernel Hardening <kernel-hardening@lists.openwall.com>, Borislav Petkov
 <bp@alien8.de>
Date: Tue, 23 Jan 2018 18:36:54 +0000
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	 <CA+55aFwcU_hHz+S9ZDphBDRQLw6pMsd+6Yp_=mQA8kTcmTzWcQ@mail.gmail.com>
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> And if we ever get CPU's that have this all fixed, we can re-visit
> introducing the fastpath. But this is all very messy and it doesn't
> seem worth it right now.

We already have CPUs it doesn't affect - older Atom for one and I
believe some or all of the VIA ones (still trying to get a definitive
confirmation).

Alan