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From: Andi Kleen <andi@firstfloor.org>
To: Andy Lutomirski <luto@kernel.org>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
        Borislav Petkov <bp@alien8.de>, Brian Gerst <brgerst@gmail.com>,
        Andrew Cooper <andrew.cooper3@citrix.com>,
        Juergen Gross <jgross@suse.com>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Kees Cook <keescook@chromium.org>
Subject: Re: [RFC 00/17] Pile o' entry stack changes
References: <cover.1504733277.git.luto@kernel.org>
Date: Wed, 06 Sep 2017 15:16:48 -0700
In-Reply-To: <cover.1504733277.git.luto@kernel.org> (Andy Lutomirski's message
        of "Wed, 6 Sep 2017 14:36:45 -0700")
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Andy Lutomirski <luto@kernel.org> writes:
>
>  - Lots of people (Linus included) have asked to convert the entry
>    code to pop registers on exit instead of movqing them off the
>    stack.  This makes a bunch of progress in that direction.

You should benchmark it on Atoms. Likely it's a regression there
because they don't have the special PUSH/POP acceleration.

-Andi