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Subject: Re: [PATCH 1/1 v2] x86: pkey-mprotect must allow pkey-0
To: Ram Pai <linuxram@us.ibm.com>
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From: Dave Hansen <dave.hansen@intel.com>
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Date: Wed, 14 Mar 2018 11:58:29 -0700
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On 03/14/2018 11:54 AM, Ram Pai wrote:
>>> (e) it bypasses key-permission checks when assigned.
>> I don't think this is necessary.  I think the only rule we *need* is:
>>
>> 	pkey-0 is allocated implicitly at execve() time.  You do not
>> 	need to call pkey_alloc() to allocate it.
> And can be explicitly associated with any address range ?

Yes, it should ideally be available for use just like any other key when
allocated.