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Subject: Re: [PATCH v3 03/13] x86/retpoline/entry: Convert entry assembler
 indirect jumps
To: David Woodhouse <dwmw@amazon.co.uk>, ak@linux.intel.com
References: <1515058213.12987.89.camel@amazon.co.uk>
 <20180104143710.8961-3-dwmw@amazon.co.uk>
Cc: Paul Turner <pjt@google.com>, LKML <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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From: Dave Hansen <dave.hansen@intel.com>
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Date: Thu, 4 Jan 2018 06:46:33 -0800
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On 01/04/2018 06:37 AM, David Woodhouse wrote:
> KPTI complicates this a little; the one in entry_SYSCALL_64_trampoline
> can't just jump to the thunk because the thunk isn't mapped. So it gets
> its own copy of the thunk, inline.

This one call site isn't too painful, of course.

But, is there anything keeping us from just sticking the thunk in the
entry text section where it would be available while still in the
trampoline?