Subject: Re: [PATCH 2/2] selftests: vm: pkeys: Fix powerpc access right updates

From: Florian Weimer <[email-masked]>
Date: Fri, 08 May 2020 22:03:20 +0200

* Sandipan Das:

> Hi Florian,
>
> On 08/05/20 11:31 pm, Florian Weimer wrote:
>> * Sandipan Das:
>> 
>>> The Power ISA mandates that all writes to the Authority
>>> Mask Register (AMR) must always be preceded as well as
>>> succeeded by a context-synchronizing instruction. This
>>> applies to both the privileged and unprivileged variants
>>> of the Move To AMR instruction.
>> 
>> Ugh.  Do you have a reference for that?
>> 
>> We need to fix this in glibc.
>> 
>
> This is from Table 6 of Chapter 11 in page 1134 of Power
> ISA 3.0B. The document can be found here:
> https://ibm.ent.box.com/s/1hzcwkwf8rbju5h9iyf44wm94amnlcrv

Thanks a lot!  I filed:

  <https://sourceware.org/bugzilla/show_bug.cgi?id=25954>

Florian