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Subject: Re: [PATCH v2] sparc64: Add support for Application Data Integrity
 (ADI)
To: Khalid Aziz <khalid.aziz@oracle.com>, David Miller <davem@davemloft.net>
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From: Rob Gardner <rob.gardner@oracle.com>
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Date: Mon, 7 Mar 2016 15:32:47 -0800
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On 03/07/2016 10:24 AM, Khalid Aziz wrote:
>
> 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.
>

I don't understand this. The hardware isn't involved  when a mapping for 
a virtual address is removed from the TSB, so how could it automatically 
clear tags?

Rob