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Date: Thu, 29 Jan 2015 16:26:10 -0500
From: Rik van Riel <riel@redhat.com>
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To: Oleg Nesterov <oleg@redhat.com>, Dave Hansen <dave.hansen@linux.intel.com>
CC: Suresh Siddha <sbsiddha@gmail.com>, Andy Lutomirski <luto@amacapital.net>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Fenghua Yu <fenghua.yu@intel.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/3] x86, fpu: unlazy_fpu: don't reset thread.fpu_counter
References: <54C2A245.4010307@redhat.com> <20150129210723.GA31584@redhat.com> <20150129210752.GB31584@redhat.com>
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On 01/29/2015 04:07 PM, Oleg Nesterov wrote:
> It is not clear why the "else" branch clears ->fpu_counter, this makes
> no sense.
> 
> If use_eager_fpu() then this has no effect. Otherwise, if we actually
> wanted to prevent fpu preload after the context switch we would need to
> reset it unconditionally, even if __thread_has_fpu().
> 
> Signed-off-by: Oleg Nesterov <oleg@redhat.com>

Reviewed-by: Rik van Riel <riel@redhat.com>