From: Jiri Olsa <olsajiri@gmail.com>
To: Jiri Pirko <jiri@resnulli.us>
Cc: Jiri Olsa <olsajiri@gmail.com>, bpf@vger.kernel.org
Subject: Re: kfunc use newbie question
Date: Mon, 30 Oct 2023 14:19:41 +0100 [thread overview]
Message-ID: <ZT+tbVP29nH29gbh@krava> (raw)
In-Reply-To: <ZT+NNS1kgBRdfZnW@nanopsycho>
On Mon, Oct 30, 2023 at 12:02:13PM +0100, Jiri Pirko wrote:
> Mon, Oct 30, 2023 at 11:14:51AM CET, olsajiri@gmail.com wrote:
> >On Mon, Oct 30, 2023 at 10:35:59AM +0100, Jiri Pirko wrote:
> >> Hi BPF :)
> >>
> >> I'm trying to use bpf_dynptr_from_skb() kfunc in my program. I compiled
> >> it with having following declaration in the bpf .c file:
> >> extern int bpf_dynptr_from_skb(struct __sk_buff *skb, __u64 flags,
> >> struct bpf_dynptr *ptr__uninit) __ksym;
> >>
> >> I have all "BPF/BTF" kernel config options on. During load,
> >> I'm still getting:
> >>
> >> libbpf: failed to find BTF for extern 'bpf_dynptr_from_skb': -3
> >
> >heya,
> >error -3 suggests there's no BTF generated, is there .BTF section
> >in the object ? did you compile with -g ?
>
> w/o -g. If I compile with -g, I'm getting this:
> libbpf: failed to find valid kernel BTF
> libbpf: Error loading vmlinux BTF: -3
hum, this one seems straightforward missing vmlinux btf,
(check btf__load_vmlinux_btf in tools/lib/bpf/btf.c)
could you please send your .config?
jirka
>
>
> >
> >jirka
> >
> >>
> >> I'm pretty much clueless about what may be wrong. Documentation didn't
> >> help me either :/
> >>
> >> Any idea what I may be doing wrong?
> >>
> >> Thanks
> >>
> >> Jiri
> >>
next prev parent reply other threads:[~2023-10-30 13:19 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-10-30 9:35 kfunc use newbie question Jiri Pirko
2023-10-30 10:14 ` Jiri Olsa
2023-10-30 11:02 ` Jiri Pirko
2023-10-30 13:19 ` Jiri Olsa [this message]
2023-10-30 13:45 ` Jiri Pirko
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