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 for <linuxppc-dev@lists.ozlabs.org>; Sat,  5 May 2018 05:59:29 +1000 (AEST)
Subject: Re: [PATCH v3] powerpc, pkey: make protection key 0 less special
To: Ram Pai <linuxram@us.ibm.com>, mpe@ellerman.id.au
References: <1525461778-26265-1-git-send-email-linuxram@us.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org, benh@kernel.crashing.org,
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 Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@kernel.org>,
 Andrew Morton <akpm@linux-foundation.org>
From: Dave Hansen <dave.hansen@intel.com>
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Date: Fri, 4 May 2018 12:59:27 -0700
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On 05/04/2018 12:22 PM, Ram Pai wrote:
> @@ -407,9 +414,6 @@ static bool pkey_access_permitted(int pkey, bool write, bool execute)
>  	int pkey_shift;
>  	u64 amr;
>  
> -	if (!pkey)
> -		return true;
> -
>  	if (!is_pkey_enabled(pkey))
>  		return true;

Looks fine to me.  Obviously doesn't have any impact on x86 or the
generic code.

One question, though.  Which other check makes up for this removed !pkey
check?