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Subject: Re: pkeys on POWER: Access rights not reset on execve
References: <20180520060425.GL5479@ram.oc3035372033.ibm.com>
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From: Florian Weimer <fweimer@redhat.com>
Message-ID: <2858a8eb-c9b5-42ce-5cfc-74a4b3ad6aa9@redhat.com>
Date: Fri, 8 Jun 2018 07:53:51 +0200
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Sender: owner-linux-mm@kvack.org
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To: Ram Pai <linuxram@us.ibm.com>
Cc: Linux-MM <linux-mm@kvack.org>, linuxppc-dev <linuxppc-dev@lists.ozlabs.org>, Andy Lutomirski <luto@kernel.org>, Dave Hansen <dave.hansen@intel.com>

On 06/08/2018 04:34 AM, Ram Pai wrote:
>>
>> So the remaining question at this point is whether the Intel
>> behavior (default-deny instead of default-allow) is preferable.
> 
> Florian, remind me what behavior needs to fixed?

See the other thread.  The Intel register equivalent to the AMR by 
default disallows access to yet-unallocated keys, so that threads which 
are created before key allocation do not magically gain access to a key 
allocated by another thread.

Thanks,
Florian