lkml.org 
[lkml]   [2018]   [Jan]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 05/23] x86, kaiser: unmap kernel from userspace page tables (core patch)
From
Date
On 01/04/2018 10:16 PM, Yisheng Xie wrote:
> BTW, we have just reported a bug caused by kaiser[1], which looks like
> caused by SMEP. Could you please help to have a look?
>
> [1] https://lkml.org/lkml/2018/1/5/3

Please report that to your kernel vendor. Your EFI page tables have the
NX bit set on the low addresses. There have been a bunch of iterations
of this, but you need to make sure that the EFI kernel mappings don't
get _PAGE_NX set on them. Look at what __pti_set_user_pgd() does in
mainline.

\
 
 \ /
  Last update: 2018-01-05 07:30    [W:0.168 / U:0.700 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site