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Subject: Re: [RFC PATCH v3 04/12] Validate r1 value before going to host
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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Paul Mackerras <paulus@samba.org>
Date: Mon, 09 Sep 2013 19:26:35 +1000
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Cc: Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com>,
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On Mon, 2013-09-09 at 15:29 +1000, Paul Mackerras wrote:
> Are we guaranteed that Sapphire will keep the stack pointer positive
> at all times?  (More a question for Ben H than you.)

Good point, we *might* eventually set the top bit..

Ben.