From:   =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>
To:     Pu Lehui <pulehui@huaweicloud.com>, bpf@vger.kernel.org,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Song Liu <song@kernel.org>, Yonghong Song <yhs@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>,
        Pu Lehui <pulehui@huawei.com>,
        Pu Lehui <pulehui@huaweicloud.com>
Subject: Re: [PATCH bpf-next v2] riscv, bpf: Add kfunc support for RV64
In-Reply-To: <20230220083203.2988238-1-pulehui@huaweicloud.com>
References: <20230220083203.2988238-1-pulehui@huaweicloud.com>
Date:   Mon, 20 Feb 2023 15:34:39 +0100
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Pu Lehui <pulehui@huaweicloud.com> writes:

> From: Pu Lehui <pulehui@huawei.com>
>
> As another important missing piece of RV64 JIT, kfunc allow bpf programs
> call kernel functions. For now, RV64 is sufficient to enable it.

Thanks Lehui!

Maybe we can reword/massage the commit message a bit? What do you think
about something like:

"Now that the BPF trampoline is supported by RISC-V, it is possible to
use BPF programs with kfunc calls.

Note that the trampoline functionality is only supported by RV64.

Add bpf_jit_supports_kfunc_call() to the 64-bit JIT."


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