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Subject: Re: [RFC] [PATCH] powerpc: Add MSR_DE to MSR_KERNEL
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Joakim Tjernlund <joakim.tjernlund@transmode.se>
Date: Sun, 03 Jun 2012 07:21:16 +1000
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On Sat, 2012-06-02 at 20:29 +0200, Joakim Tjernlund wrote:
> 
> hmm, where does this go w.r.t the patch? Got the feeling that the
> best thing is to just turn MSR:DE on and be done with it? 

Not unconditionally, we need to have a close look, that might be ok
specifically for BookE 32-bit, it's certainly not ok for BookE 64-bit at
this point.

For now, I'm ok with a debug CONFIG_* option.

Also do we know if MSR:DE has any performance impact on any CPU ? I know
having DACs enabled has a major impact on some for example.

Ben.