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Date: Tue, 8 Nov 2016 13:05:42 +0100
From: Heiko Carstens <heiko.carstens@de.ibm.com>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Rutland <mark.rutland@arm.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
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        Andrew Morton <akpm@linux-foundation.org>,
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Subject: Re: [PATCH] mm: only enable sys_pkey* when ARCH_HAS_PKEYS
References: <1477958904-9903-1-git-send-email-mark.rutland@arm.com>
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On Tue, Nov 08, 2016 at 12:39:28PM +0100, Arnd Bergmann wrote:
> On Tuesday, November 8, 2016 10:30:42 AM CET Heiko Carstens wrote:
> > Three architectures (parisc, powerpc, s390) decided to ignore the system
> > calls completely, but still have the pkey code linked into the kernel
> > image.
> 
> Wouldn't it actually make sense to hook this up to the storage keys
> in the s390 page tables?

We have storage keys per _physical_ page. Not per page within the the table
entries. So this doesn't work unfortunately.