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 17:21:05 -0700
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On 03/07/2016 12:16 PM, David Miller wrote:
> From: Khalid Aziz <khalid.aziz@oracle.com>
> Date: Mon, 7 Mar 2016 11:24:54 -0700
>
>> Tags can be cleared by user by setting tag to 0. Tags are
>> automatically cleared by the hardware when the mapping for a virtual
>> address is removed from TSB (which is why swappable pages are a
>> problem), so kernel does not have to do it as part of clean up.
>
> You might be able to crib some bits for the Tag in the swp_entry_t, it's
> 64-bit and you can therefore steal bits from the offset field.
>
> That way you'll have the ADI tag in the page tables, ready to re-install
> at swapin time.
>

Hi Dave,

Can we enable ADI support for swappable pages in a subsequent update 
after the core functionality is stable on mlock'd pages?

Thanks,
Khalid