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Subject: Re: [PATCH v3] powerpc, pkey: make protection key 0 less special
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From: Dave Hansen <dave.hansen@intel.com>
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On 05/04/2018 02:26 PM, Michal Suchánek wrote:
> If it is not ok to change permissions of pkey 0 is it ok to free it?

It's pretty much never OK to free it on x86 or ppc.  But, we're not
going to put code in to keep userspace from shooting itself in the foot,
at least on x86.