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Subject: Re: [PATCH] [v4] x86/doc: add PTI description
To: Dave Hansen <dave.hansen@linux.intel.com>,
        linux-kernel@vger.kernel.org
Cc: x86@kernel.org, keescook@chromium.org, moritz.lipp@iaik.tugraz.at,
        daniel.gruss@iaik.tugraz.at, michael.schwarz@iaik.tugraz.at,
        richard.fellner@student.tugraz.at, luto@kernel.org,
        torvalds@linux-foundation.org, hughd@google.com
References: <20180105174436.1BC6FA2B@viggo.jf.intel.com>
From: Randy Dunlap <rdunlap@infradead.org>
Message-ID: <c046dd06-54fa-a4e6-b0eb-25716c4beba4@infradead.org>
Date: Fri, 5 Jan 2018 10:01:35 -0800
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On 01/05/2018 09:44 AM, Dave Hansen wrote:
> Changes from v3:
>  * Increasingly minor text fixes.

Yeah.  Just merge it and use patches for anything else.
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>

Thanks.

> Changes from v2:
>  * Update some wording
>  * Minor typo and grammar fixes
>  * Further clarify what INVPCID is.
> 
> Changes from v1:
>  * update kernel-parameters.txt to clarify that the pti= option
>    is not just for disabling.  Also describe what 'pti=auto' does
>    and why
>  * Add a note about the presence of NX in the user portion of the
>    kernel page tables
>  * Clarify _additional_ 4k of PGD space
>  * Add a note about the runtime overhead of PCID without INVPCID
> 
> ---
> 
> From: Dave Hansen <dave.hansen@linux.intel.com>
> 
> Add some details about how PTI works, what some of the downsides
> are, and how to debug it when things go wrong.
> 
> Also document the kernel parameter: 'nopti'.
> 
> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
> Reviewed-by: Kees Cook <keescook@chromium.org>
> Cc: Moritz Lipp <moritz.lipp@iaik.tugraz.at>
> Cc: Daniel Gruss <daniel.gruss@iaik.tugraz.at>
> Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at>
> Cc: Richard Fellner <richard.fellner@student.tugraz.at>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: Linus Torvalds <torvalds@linux-foundation.org>
> Cc: Hugh Dickins <hughd@google.com>
> Cc: x86@kernel.org
> ---
> 
>  b/Documentation/admin-guide/kernel-parameters.txt |   21 +-
>  b/Documentation/x86/pti.txt                       |  186 ++++++++++++++++++++++
>  2 files changed, 200 insertions(+), 7 deletions(-)


-- 
~Randy