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Date:   Sun, 10 Jul 2022 20:58:17 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Yixun Lan <dlan@gentoo.org>
Cc:     Christoph Hellwig <hch@infradead.org>, Yonghong Song <yhs@fb.com>,
        Andrii Nakryiko <andrii.nakryiko@gmail.com>,
        Alan Maguire <alan.maguire@oracle.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        linux-riscv@lists.infradead.org,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
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        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        open list <linux-kernel@vger.kernel.org>,
        Networking <netdev@vger.kernel.org>, bpf <bpf@vger.kernel.org>
Subject: Re: [PATCH] RISC-V/bpf: Enable bpf_probe_read{, str}()
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On Sat, Jul 09, 2022 at 04:48:05PM +0800, Yixun Lan wrote:
> never mind, I think the logic is quite clear, we can do something in bcc:
> 
> 1) adopt new _{kernel,user} interface whenever possible, this will
> work fine for all arch with new kernel versions
> 
> 2) for old kernel versions which lack the _{kernel,user} support,
> fall back to old bpf_probe_read(), but take care of the Archs which
> have overlaping address space - like s390, and just error out for it

Yes, that is the right thing to do.