Subject: Re: [PATCH v2] sparc64: Add support for Application Data Integrity
 (ADI)
To: David Miller <davem@davemloft.net>
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From: Khalid Aziz <khalid.aziz@oracle.com>
Organization: Oracle Corp
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Date: Mon, 7 Mar 2016 15:30:23 -0700
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On 03/07/2016 02:34 PM, David Miller wrote:
> From: Khalid Aziz <khalid.aziz@oracle.com>
> Date: Mon, 7 Mar 2016 14:27:09 -0700
>
>> I agree with your point of view. PSTATE.mcde and TTE.mcd are set in
>> response to request from userspace. If userspace asked for them to be
>> set, they already know but it was the database guys that asked for
>> these two functions and they are the primary customers for the ADI
>> feature. I am not crazy about this idea since this extends the
>> mprotect API even further but would you consider using the return
>> value from mprotect to indicate if PSTATE.mcde or TTE.mcd were already
>> set on the given address?
>
> Well, that's the idea.
>
> If the mprotect using MAP_ADI or whatever succeeds, then ADI is
> enabled.
>
> Users can thus also pass MAP_ADI as a flag to mmap() to get ADI
> protection from the very beginning.
>

MAP_ADI has been sitting in my backlog for some time. Looks like you 
just raised its priority ;)

--
Khalid