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From: "Toke Høiland-Jørgensen" <toke@redhat.com>
To: Kenny Ho <y2kenny@gmail.com>, bpf <bpf@vger.kernel.org>
Subject: Re: bpf helper functions from kernel module
Date: Thu, 22 Apr 2021 18:43:14 +0200	[thread overview]
Message-ID: <87czumfexp.fsf@toke.dk> (raw)
In-Reply-To: <CAOWid-eY4CHZw01d9w3KC0qpodWmTXfQqLopkNFVNwZhmCYgMQ@mail.gmail.com>

Kenny Ho <y2kenny@gmail.com> writes:

> Hi,
>
> From https://www.collabora.com/news-and-blog/blog/2019/04/15/an-ebpf-overview-part-2-machine-and-bytecode/
> "The BPF-accesible kernel "helper" functions are defined by the kernel
> core (not extensible through modules) via an API similar to defining
> syscalls"
>
> Has there been interest/discussion around having helper functions from
> kernel modules?  Going through the code, I am guessing one of the
> obstacles is to have the verifier checking against helper functions
> that may or may not be available but I am not an expert of the
> subsystem.  What are the current opinions on having helper functions
> from kernel modules?

The support for calling kernel functions directly (AKA "unstable
helpers") will likely be the way this will be achievable. See the
comment in brackets half-way down in the description here:

https://lore.kernel.org/bpf/20210325015142.1544736-1-kafai@fb.com/

-Toke


  reply	other threads:[~2021-04-22 16:43 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-22 15:43 bpf helper functions from kernel module Kenny Ho
2021-04-22 16:43 ` Toke Høiland-Jørgensen [this message]
2021-04-23 13:41   ` Kenny Ho

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