linux-kernel - Re: [PATCH v2] x86/fpu: Disable BH while while loading FPU registers in __fpu__restore

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Message-ID: <f749145d-622e-cd89-7484-f5373da7b86e@intel.com>
Date:   Mon, 19 Nov 2018 09:32:44 -0800
From:   Dave Hansen <dave.hansen@...el.com>
To:     Borislav Petkov <bp@...en8.de>,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Cc:     x86@...nel.org, Ingo Molnar <mingo@...nel.org>,
        linux-kernel@...r.kernel.org, Andy Lutomirski <luto@...nel.org>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Radim Krčmář <rkrcmar@...hat.com>,
        kvm@...r.kernel.org, "Jason A. Donenfeld" <Jason@...c4.com>,
        Rik van Riel <riel@...riel.com>,
        Dave Hansen <dave.hansen@...ux.intel.com>
Subject: Re: [PATCH v2] x86/fpu: Disable BH while while loading FPU registers
 in __fpu__restore_sig()

On 11/19/18 9:27 AM, Borislav Petkov wrote:
>>> I was really hoping for code comments. :)
>> I though we agreed to make those in the larger series because those
>> comments in __fpu__restore_sig() would be removed anyway (as part of the
>> series).
> Also, over local_bh_disable() does not really fit as this is generic
> code and Sebastian said ARM does the whole thing a bit differently, for
> one.
> 
> We probably should put that comment somewhere prominent in
> arch/x86/kernel/fpu/core.c or similar - somewhere people poking at FPU
> stuff will see it.

Ahh, got it.

arch/x86/kernel/fpu/core.c would be a fine spot.