From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Hansen <dave.hansen@linux.intel.com>
Subject: Re: [PATCH 04/11] x86/fpu: eager switch PKRU state
Date: Fri, 12 Oct 2018 12:44:39 -0700
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Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
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        Paolo Bonzini <pbonzini@redhat.com>,
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To: Andy Lutomirski <luto@kernel.org>
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On 10/12/2018 11:09 AM, Andy Lutomirski wrote:
> But maybe WRPKRU is more expensive than RDPKRU and a branch?

Yeah, it is more expensive.  It has a higher cycle cost and it's also
practically a (light) speculation barrier.