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Message-ID: <c88e73b2-69cf-4f74-2776-3644f48edfe5@intel.com>
Date:   Thu, 16 Jun 2022 12:31:02 -0700
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Subject: Re: [RFC PATCH 4/6] pkeys: Lift pkey hardware check for pkey_alloc()
Content-Language: en-US
To:     <ira.weiny@intel.com>, <linux-api@vger.kernel.org>
CC:     <ahaas@chromium.org>, <clemensb@chromium.org>,
        <gdeepti@chromium.org>, <jkummerow@chromium.org>,
        <manoskouk@chromium.org>, <thibaudm@chromium.org>,
        Florian Weimer <fweimer@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>,
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        <linux-kselftest@vger.kernel.org>
References: <20220610233533.3649584-1-ira.weiny@intel.com>
 <20220610233533.3649584-5-ira.weiny@intel.com>
From:   Sohil Mehta <sohil.mehta@intel.com>
In-Reply-To: <20220610233533.3649584-5-ira.weiny@intel.com>
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> diff --git a/mm/mprotect.c b/mm/mprotect.c
> index ba5592655ee3..56d35de33725 100644
> --- a/mm/mprotect.c
> +++ b/mm/mprotect.c
> @@ -773,6 +773,9 @@ SYSCALL_DEFINE2(pkey_alloc, unsigned long, flags, unsigned long, init_val)
>   	int pkey;
>   	int ret;
>   
> +	if (!arch_pkeys_enabled())
> +		return -ENOSPC;
> +

See comments in patch 3/6. Since we are modifying (fixing) old behavior, 
should we just return ENOSYS to make this consistent?

Sohil

>   	/* No flags supported yet. */
>   	if (flags)
>   		return -EINVAL;