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Date: Sat, 23 Jan 2016 18:51:14 +0100
From: Borislav Petkov <bp@alien8.de>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>, X86 ML <x86@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Fenghua Yu <fenghua.yu@intel.com>, Oleg Nesterov <oleg@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
        yu-cheng yu <yu-cheng.yu@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Rik van Riel <riel@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 1/5] x86/fpu: Fix math emulation in eager fpu mode
Message-ID: <20160123175114.GE16329@pd.tnic>
References: <cover.1453510332.git.luto@kernel.org>
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On Sat, Jan 23, 2016 at 09:40:06AM -0800, Andy Lutomirski wrote:
> I'm confused.  I want to make use_eager_fpu() return true always, so
> how would this help?  The idea is for FPU emulation to work despite
> being in eager mode.

I mean this:

static __always_inline __pure bool use_eager_fpu(void)
{
	if (!static_cpu_has(X86_FEATURE_FPU))
		return false;

        return static_cpu_has(X86_FEATURE_EAGER_FPU);
}

Although now I realize that returning false is ambiguous here. F'get it.

-- 
Regards/Gruss,
    Boris.

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