Re: [PATCH V6 00/10] PKS: Add Protection Key Supervisor support

[Ira Weiny]

On Fri, Apr 16, 2021 at 03:14:56PM -0700, 'Ira Weiny' wrote:
> On Thu, Apr 01, 2021 at 03:58:23PM -0700, 'Ira Weiny' wrote:
> > From: Ira Weiny <ira.weiny@xxxxxxxxx>
> > 
> > Introduce a new page protection mechanism for supervisor pages, Protection Key
> > Supervisor (PKS).
> 
> Is there any feedback on this series?

Please disregard this series...  (If you have not done so already).

Along with Rick posting his RFC for page table protections[1] he has raised a
concern with me about pkeys being allocated and then reallocated to another
user.  It turns out the code has a bug in this area and the fix is not trivial.

Because the PMEM use case never needed to free its key and even if it did a
small window of access was not a concern this was not tested.

The best solutions involve changing the API therefore this series is going to
need a respin.

Thank you,
Ira

[1] https://lore.kernel.org/lkml/20210505003032.489164-1-rick.p.edgecombe@xxxxxxxxx/