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From:   "Bae, Chang Seok" <chang.seok.bae@intel.com>
To:     "Hansen, Dave" <dave.hansen@intel.com>
CC:     Andy Lutomirski <luto@kernel.org>, Borislav Petkov <bp@suse.de>,
        "Thomas Gleixner" <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>, X86 ML <x86@kernel.org>,
        "Brown, Len" <len.brown@intel.com>,
        "Liu, Jing2" <jing2.liu@intel.com>,
        "Shankar, Ravi V" <ravi.v.shankar@intel.com>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v5 14/28] x86/fpu/xstate: Prevent unauthorised use of
 dynamic user state
Thread-Topic: [PATCH v5 14/28] x86/fpu/xstate: Prevent unauthorised use of
 dynamic user state
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Date:   Wed, 16 Jun 2021 19:37:49 +0000
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On Jun 16, 2021, at 12:28, Hansen, Dave <dave.hansen@intel.com> wrote:
> That's odd.  How is it possible that the performance of XGETBV(1)
> informed the design of that patch without there being any mention of
> XGETBV in the comments or changelog?

Yes, I admit that it is wrong that the text there highlights the benefit
without fairly mentioning the cost. I will make sure v6 covers them all.

Thanks,
Chang