From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Hansen <dave.hansen@linux.intel.com>
Subject: Re: [PATCH 07/11] x86/pkeys: Drop the preempt-disable section
Date: Fri, 12 Oct 2018 10:58:42 -0700
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References: <20181004140547.13014-1-bigeasy@linutronix.de>
 <20181004140547.13014-8-bigeasy@linutronix.de>
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Cc: x86@kernel.org, Andy Lutomirski <luto@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        kvm@vger.kernel.org, "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Rik van Riel <riel@surriel.com>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        linux-kernel@vger.kernel.org
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On 10/04/2018 07:05 AM, Sebastian Andrzej Siewior wrote:
> The fpu->initialized flag should not be changed underneath us. This might be a
> fallout during the removal of the LazyFPU support. The FPU is marked
> initialized as soon as the state has been set to an initial value. It does not
> signal if the CPU's FPU registers are loaded.

If this is true, then the check for fpu->initialized should also go away.

If we were paranoid, we might also add a WARN_ON_ONCE() to make sure our
assumption holds true.