Re: [PATCH 1/9] x86, pkeys: do not special case protection key 0

[Shuah Khan]

On 03/26/2018 11:53 AM, Dave Hansen wrote:
> On 03/26/2018 10:47 AM, Shuah Khan wrote:
>>
>> Also what happens "pkey_free() pkey-0" - can you elaborate more on that
>> "silliness consequences"
> 
> It's just what happens if you free any other pkey that is in use: it
> might get reallocated later.  The most likely scenario is that you will
> get pkey-0 back from pkey_alloc(), you will set an access-disable or
> write-disable bit in PKRU for it, and your next stack access will SIGSEGV.
> 

Thanks. This will good information to include in the commit log.

-- Shuah