Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 12:06 PM, Ram Pai wrote:

On Fri, Mar 09, 2018 at 09:19:53PM +1100, Michael Ellerman wrote:

quoted

Ram Pai [off-list ref] writes:

quoted

Once an address range is associated with an allocated pkey, it cannot be
reverted back to key-0. There is no valid reason for the above behavior.  On
the contrary applications need the ability to do so.

Please explain this in much more detail. Is it an ABI change?

Not necessarily an ABI change. older binary applications  will continue
to work. It can be considered as a bug-fix.

Yeah, agreed.  I do not think this is an ABI change.