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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>
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        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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> 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