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Date:   Fri, 20 Apr 2018 10:19:36 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Yonghong Song <yhs@fb.com>
Cc:     mingo@kernel.org, ast@fb.com, daniel@iogearbox.net,
        linux-kernel@vger.kernel.org, x86@kernel.org, kernel-team@fb.com
Subject: Re: [PATCH v2] x86/cpufeature: guard asm_volatile_goto usage with
 NO_BPF_WORKAROUND
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References: <20180415042738.1788215-1-yhs@fb.com>
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On Sat, Apr 14, 2018 at 09:27:38PM -0700, Yonghong Song wrote:

> This patch adds a preprocessor guard NO_BPF_WORKAROUND around the
> asm_volatile_goto based static_cpu_has(). NO_BPF_WORKAROUND is set
> at toplevel Makefile when compiler supports asm-goto. That is,
> if the compiler supports asm-goto, the kernel build will use
> asm-goto version of static_cpu_has().

Hurm, so adding __BPF__ for BPF compiles isn't an option? It seems to me
having a CPP flag to identify BPF compile context might be useful in
general.