ACK: [PATCH 0/3][B] Insufficient shootdown for paging-structure caches (LP: #1798897)

[Kleber Souza]

On 10/20/18 00:38, Tyler Hicks wrote:
> BugLink: https://launchpad.net/bugs/1798897
> 
> [Impact]
> 
> Paging structure caches are not always flushed as part of a TLB shootdown
> operation on x86. See the Project Zero writeup for more details:
> 
>   https://bugs.chromium.org/p/project-zero/issues/detail?id=1633
> 
> [Test Case]
> 
> Ideally, we'd be able to use the test case described in the Project Zero bug
> report. However, it depends on certain processor features as well as custom
> kernel changes to make the proof-of-concept more likely to be successful.
> 
> Instead, I think we're limited to simple boot testing and then will need to
> rely on our regular SRU testing.
> 
> [Regression Potential]
> 
> Considerable since the changes are in mm/ but these three patches have been
> released in the upstream linux-stable trees for a while now.
> 
> 
> This issue is worthy of a CVE ID and it is my undersatnding that Jann is going
> to request one but we should move forward with reviewing/applying these patches
> in the meantime.
> 
> These patches are already present in the Cosmic kernel. This issue does not
> affect kernels older than Bionic's kernel.
> 
> Tyler
> 
> 

Clean cherry-picks, already present in Bionic and upstream stable and
they don't seem to have follow-up fixes. So it looks safe to pull them in:

Acked-by: Kleber Sacilotto de Souza <kleber.souza at canonical.com>