From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Gilad Reti <gilad.reti@gmail.com>,
Andrii Nakryiko <andrii@kernel.org>, bpf <bpf@vger.kernel.org>,
Networking <netdev@vger.kernel.org>,
Alexei Starovoitov <ast@fb.com>,
Daniel Borkmann <daniel@iogearbox.net>,
Kernel Team <kernel-team@fb.com>
Subject: Re: [PATCH bpf-next 3/3] selftests/bpf: add tests for user- and non-CO-RE BPF_CORE_READ() variants
Date: Thu, 7 Jan 2021 12:00:14 -0800 [thread overview]
Message-ID: <20210107200014.ijpg3n7mjqdrrrvo@ast-mbp> (raw)
In-Reply-To: <CAEf4BzZay-ofoZ-RURa0vTyQnEVaqF4_xuTAijSA9wgm=kt02g@mail.gmail.com>
On Wed, Jan 06, 2021 at 03:25:30PM -0800, Andrii Nakryiko wrote:
> >
> > If I am not mistaken (which is completely possible), I think that
> > providing such a macro will
> > not cause any more confusion than the bpf_probe_read_{,user}
> > distinction already does,
> > since BPF_CORE_READ_USER to BPF_CORE_READ is the same as bpf_probe_read_user
> > to bpf_probe_read.
>
> I think the biggest source of confusion is that USER part in
> BPF_CORE_READ_USER refers to reading data from user address space, not
> really user structs (which is kind of natural instinct here). CO-RE
> *always* works only with kernel types, which is obvious if you have a
> lot of experience with using CO-RE, but not initially, unfortunately.
Please send a patch to add such clarifying comment.
prev parent reply other threads:[~2021-01-07 20:00 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-18 23:56 [PATCH bpf-next 0/3] Add user-space and non-CO-RE variants of BPF_CORE_READ() Andrii Nakryiko
2020-12-18 23:56 ` [PATCH bpf-next 1/3] libbpf: add user-space variants of BPF_CORE_READ() family of macros Andrii Nakryiko
2020-12-18 23:56 ` [PATCH bpf-next 2/3] libbpf: add non-CO-RE variants of BPF_CORE_READ() macro family Andrii Nakryiko
2020-12-18 23:56 ` [PATCH bpf-next 3/3] selftests/bpf: add tests for user- and non-CO-RE BPF_CORE_READ() variants Andrii Nakryiko
2021-01-05 3:46 ` Alexei Starovoitov
2021-01-05 5:08 ` Andrii Nakryiko
2021-01-05 19:03 ` Alexei Starovoitov
2021-01-05 21:03 ` Andrii Nakryiko
2021-01-06 6:09 ` Alexei Starovoitov
2021-01-06 10:10 ` Gilad Reti
2021-01-06 23:25 ` Andrii Nakryiko
2021-01-07 20:00 ` Alexei Starovoitov [this message]
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