Re: [PATCH] RISC-V/bpf: Enable bpf_probe_read{, str}()

Yixun Lan
2022-07-09T08:48:34Z

Hi Christoph:

On 23:24 Fri 08 Jul , Christoph Hellwig wrote:
> On Sat, Jul 09, 2022 at 09:01:10AM +0800, Yixun Lan wrote:
> > Please check the ongoing discussion [0] in the bcc tools if you're
> > interested in, advice and comments are welcome
> >
> > [0] https://github.com/iovisor/bcc/pull/4085#issuecomment-1179446738
>
> I can't find a way to post there, as replying eems to require a login.
> Is there a mailing list discussion somewhere that is broadly accessible?

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

--
Yixun Lan (dlan)
Gentoo Linux Developer
GPG Key ID AABEFD55