lkml.org 
[lkml]   [2018]   [Jan]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] [v2] x86/doc: add PTI description
From
Date
On 2018-01-05 09:24, Dave Hansen wrote:
> + Not specifying this option nothing is equivalent to
> + pti=auto.

-nothing

> +Page Table Isolation (pti, previously known as KAISER[1]) is a
> +countermeasure against attacks on kernel address information such
> +as the "Meltdown" approach[2].

It's not really just address information, but any data. Maybe "attacks
that leak kernel memory"?

> +To avoid leaking address information, we create an new, independent

Same issue here. Also an -> a.

> +copy of the page tables which are used only when running userspace

are -> is. The copy is singular.

> +applications. When the kernel is entered via syscalls, interrupts or
> +exceptions, page tables are switched to the full "kernel" copy. When

"the page tables".

> +crippled by setting the NX bit in the top level. This ensures
> +that if a kernel->user CR3 switch is missed that userspace will
> +crash immediately upon executing its first instruction.

"that userspace" -> "then userspace"

--
Hector Martin "marcan" (marcan@marcan.st)
Public Key: https://mrcn.st/pub

\
 
 \ /
  Last update: 2018-01-05 02:44    [W:2.044 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site