[PATCH v9 29/51] mm/mprotect, powerpc/mm/pkeys, x86/mm/pkeys: Add sysfs interface

[Benjamin Herrenschmidt]

On Wed, 2017-12-20 at 09:50 -0800, Ram Pai wrote:
> The argument against this patch is --  it should not be baked into
> the ABI as yet, since we do not have clarity on what applications need.
> 
> As it stands today the only way to figure out the information from
> userspace is by probing the kernel through calls to sys_pkey_alloc().
> 
> AT_HWCAP can be used, but that will certainly not be capable of
> providing all the information that userspace might expect.
> 
> Your thoughts?

Well, there's one well known application wanting that whole keys
business, so why not ask them what works for them ?

In the meantime, that shouldn't block the rest of the patches.

Cheers,
Ben.