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Subject: Re: [PATCH 4/9] x86, pkeys: override pkey when moving away from
 PROT_EXEC
To:     Ram Pai <linuxram@us.ibm.com>,
        Dave Hansen <dave.hansen@linux.intel.com>
References: <20180326172721.D5B2CBB4@viggo.jf.intel.com>
 <20180326172727.025EBF16@viggo.jf.intel.com>
 <20180407000943.GA15890@ram.oc3035372033.ibm.com>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        shakeelb@google.com, stable@kernel.org, tglx@linutronix.de,
        mpe@ellerman.id.au, mingo@kernel.org, akpm@linux-foundation.org,
        shuah@kernel.org
From:   Dave Hansen <dave.hansen@intel.com>
Message-ID: <6e3f8e1c-afed-64de-9815-8478e18532aa@intel.com>
Date:   Fri, 6 Apr 2018 17:47:29 -0700
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On 04/06/2018 05:09 PM, Ram Pai wrote:
>> -	/*
>> -	 * Look for a protection-key-drive execute-only mapping
>> -	 * which is now being given permissions that are not
>> -	 * execute-only.  Move it back to the default pkey.
>> -	 */
>> -	if (vma_is_pkey_exec_only(vma) &&
>> -	    (prot & (PROT_READ|PROT_WRITE))) {
>> -		return 0;
>> -	}
>> +
> Dave,
> 	this can be simply:
> 
> 	if ((vma_is_pkey_exec_only(vma) && (prot != PROT_EXEC))
> 		return ARCH_DEFAULT_PKEY;

Yes, but we're removing that code entirely. :)