lkml.org 
[lkml]   [2023]   [Mar]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH v5 22/34] x86/fred: FRED initialization code
From
On 3/20/23 18:02, andrew.cooper3@citrix.com wrote:
> There are fewer cases where a non-IST #VE ends up in a re-entrant fault
> (IIRC, you can still manage it by unmapping the entry stack), but you're
> still trusting the outer hypervisor to not e.g. unmap the SYSCALL entry
> point.

This is a general weakness of #VE. But, the current Linux TDX guest
implementation is not vulnerable to it. If the host unmaps something
unexpectedly, the guest will just die because of ATTR_SEPT_VE_DISABLE.
No #VE:

> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/coco/tdx/tdx.c#n216


\
 
 \ /
  Last update: 2023-03-27 01:12    [W:0.076 / U:0.388 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site