Re: [PATCH] [v4] x86/doc: add PTI description

[Randy Dunlap]

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@xxxxxxxxxxxxx>

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@xxxxxxxxxxxxxxx>
> 
> 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@xxxxxxxxxxxxxxx>
> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
> Cc: Moritz Lipp <moritz.lipp@xxxxxxxxxxxxxx>
> Cc: Daniel Gruss <daniel.gruss@xxxxxxxxxxxxxx>
> Cc: Michael Schwarz <michael.schwarz@xxxxxxxxxxxxxx>
> Cc: Richard Fellner <richard.fellner@xxxxxxxxxxxxxxxxx>
> Cc: Andy Lutomirski <luto@xxxxxxxxxx>
> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> Cc: Hugh Dickins <hughd@xxxxxxxxxx>
> Cc: x86@xxxxxxxxxx
> ---
> 
>  b/Documentation/admin-guide/kernel-parameters.txt |   21 +-
>  b/Documentation/x86/pti.txt                       |  186 ++++++++++++++++++++++
>  2 files changed, 200 insertions(+), 7 deletions(-)


-- 
~Randy