lkml.org 
[lkml]   [2016]   [Jan]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH 1/2] x86/kasan: clear kasan_zero_page after TLB flush
On Mon, Jan 11, 2016 at 4:51 AM, Andrey Ryabinin
<aryabinin@virtuozzo.com> wrote:
> Currently we clear kasan_zero_page before __flush_tlb_all(). This
> works with current implementation of native_flush_tlb[_global]()
> because it doesn't cause do any writes to kasan shadow memory.
> But any subtle change made in native_flush_tlb*() could break this.
> Also current code seems doesn't work for paravirt guests (lguest).
>
> Only after the TLB flush we can be sure that kasan_zero_page is not
> used as early shadow anymore (instrumented code will not write to it).
> So it should cleared it only after the TLB flush.

This seems to fix the issue with my patch set. Thanks.

Tested-by: Andy Lutomirski <luto@kernel.org>

--Andy

\
 
 \ /
  Last update: 2016-01-19 00:01    [W:0.127 / U:1.128 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site