lkml.org 
[lkml]   [2021]   [Nov]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH Part2 v5 00/45] Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support
On Wed, Nov 24, 2021 at 09:48:14AM -0800, Dave Hansen wrote:
> That covers things like copy_from_user(). It does not account for
> things where kernel mappings are used, like where a
> get_user_pages()/kmap() is in play.

The kmap case is guarded by KVM code, which locks the page first so that
the guest can't change the page state, then checks the page state, and
if it is shared does the kmap and the access.

This should turn an RMP fault in the kernel which is not covered in the
uaccess exception table into a fatal error.

Regards,

--
Jörg Rödel
jroedel@suse.de

SUSE Software Solutions Germany GmbH
Maxfeldstr. 5
90409 Nürnberg
Germany

(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev

\
 
 \ /
  Last update: 2021-11-25 11:09    [W:0.218 / U:2.500 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site