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Subject: Re: [PATCH] pkeys: Introduce PKEY_ALLOC_SIGNALINHERIT and change
 signal semantics
To: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>, linuxram@us.ibm.com,
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From: Florian Weimer <fweimer@redhat.com>
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Date: Mon, 14 May 2018 17:34:07 +0200
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On 05/14/2018 05:32 PM, Andy Lutomirski wrote:
> 
> 
> 
>> On May 14, 2018, at 5:01 AM, Florian Weimer <fweimer@redhat.com> wrote:
>>
>>> One thing we could do, though: the current initual state on process
>>> creation is all access blocked on all keys.  We could change it so that
>>> half the keys are fully blocked and half are read-only.  Then we could add
>>> a PKEY_ALLOC_STRICT or similar that allocates a key with the correct
>>> initial state*and*  does the setsignal thing.  If there are no keys left
>>> with the correct initial state, then it fails.
>>
>> The initial PKRU value can currently be configured by the system administrator.  I fear this approach has too many moving parts to be viable.
>>
>>
> 
> Honestly, I think we should drop that option. I don’t see how we can expect an administrator to do this usefully.

I don't disagree—it makes things way less predictable in practice.

Thanks,
Florian