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Date:   Sat, 14 Apr 2018 12:11:12 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Alexei Starovoitov <ast@fb.com>
Cc:     Yonghong Song <yhs@fb.com>, 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>
Subject: Re: [PATCH] x86/cpufeature: guard asm_volatile_goto usage with
 CC_HAVE_ASM_GOTO
Message-ID: <20180414101112.GX4064@hirez.programming.kicks-ass.net>
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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.