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Subject: Re: [PATCH bpf-next 2/2] bpf: Make BPF_JIT_DEFAULT_ON selectable in
 Kconfig
To:     Tiezhu Yang <yangtiezhu@loongson.cn>,
        Alexei Starovoitov <ast@kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>
Cc:     Xuefeng Li <lixuefeng@loongson.cn>, netdev@vger.kernel.org,
        bpf@vger.kernel.org, linux-kernel@vger.kernel.org
References: <1644569851-20859-1-git-send-email-yangtiezhu@loongson.cn>
 <1644569851-20859-3-git-send-email-yangtiezhu@loongson.cn>
From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <af2b415a-874d-0524-c5bb-b50c419a1559@iogearbox.net>
Date:   Fri, 11 Feb 2022 11:23:59 +0100
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On 2/11/22 9:57 AM, Tiezhu Yang wrote:
> Currently, it is not possible to set bpf_jit_enable to 1 by default
> and the users can change it to 0 or 2, it seems bad for some users,
> make BPF_JIT_DEFAULT_ON selectable to give them a chance.

I'm not fully sure I follow the above, so you are saying that a kconfig of
!BPF_JIT_ALWAYS_ON and ARCH_WANT_DEFAULT_BPF_JIT, enables BPF_JIT_DEFAULT_ON
however in such setting you are not able to reset bpf_jit_enable back to 0 at
runtime?

Thanks,
Daniel