lkml.org 
[lkml]   [2017]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 1/5] x86/mm/kaiser: Alternative ESPFIX
From
Date
On 11/27/2017 02:31 PM, Peter Zijlstra wrote:
> Change the asm to do the CR3 switcheroo so we can remove the magic
> mappings.
>
> Since RDI is unused after SWAPGS we can use it as a scratch reg for
> SWITCH_TO_KERNEL. And once we've computed the new RSP (in RAX) we no
> longer need RDI and can again use it as scratch reg for
> SWITCH_TO_USER.

This definitely looks like the right thing. Either I missed something
obvious before, or Andy's entry rework made this much more obviously
correct to do the simple thing here.

\
 
 \ /
  Last update: 2017-11-27 23:42    [W:0.103 / U:0.044 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site