From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yonghong Song <yhs@fb.com>
Subject: Re: [PATCH] x86/cpufeature: guard asm_volatile_goto usage with
 CC_HAVE_ASM_GOTO
Date: Sat, 14 Apr 2018 13:30:56 -0700
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Cc: <mingo@kernel.org>, <daniel@iogearbox.net>,
        <linux-kernel@vger.kernel.org>, <x86@kernel.org>,
        <kernel-team@fb.com>, Thomas Gleixner <tglx@linutronix.de>,
        netdev <netdev@vger.kernel.org>,
        Jesper Dangaard Brouer <brouer@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>,
        Alexei Starovoitov <ast@fb.com>
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On 4/14/18 3:11 AM, Peter Zijlstra wrote:
> On Fri, Apr 13, 2018 at 01:42:14PM -0700, Alexei Starovoitov wrote:
>> On 4/13/18 11:19 AM, Peter Zijlstra wrote:
>>> On Tue, Apr 10, 2018 at 02:28:04PM -0700, Alexei Starovoitov wrote:
>>>> Instead of
>>>> #ifdef CC_HAVE_ASM_GOTO
>>>> we can replace it with
>>>> #ifndef __BPF__
>>>> or some other name,
>>>
>>> I would prefer the BPF specific hack; otherwise we might be encouraging
>>> people to build the kernel proper without asm-goto.
>>>
>>
>> I don't understand this concern.
> 
> The thing is; this will be a (temporary) BPF specific hack. Hiding it
> behind something that looks 'normal' (CC_HAVE_ASM_GOTO) is just not
> right.

This is a fair concern. I will use a different macro and send v2 soon.
Thanks.