From: Jesper Dangaard Brouer <brouer@redhat.com>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Sebastiano Miano <sebastiano.miano@polito.it>,
netdev@vger.kernel.org, ast@kernel.org, daniel@iogearbox.net,
mingo@redhat.com, rostedt@goodmis.org, fulvio.risso@polito.it,
"David S. Miller" <davem@davemloft.net>,
brouer@redhat.com
Subject: Re: [bpf-next PATCH 3/3] bpf: add sample program to trace map events
Date: Mon, 23 Apr 2018 22:22:38 +0200 [thread overview]
Message-ID: <20180423222238.2636bdc8@redhat.com> (raw)
In-Reply-To: <20180423200801.m2kcrjcoavuibbmk@ast-mbp>
On Mon, 23 Apr 2018 14:08:02 -0600
Alexei Starovoitov <alexei.starovoitov@gmail.com> wrote:
> On Mon, Apr 23, 2018 at 04:08:36PM +0200, Sebastiano Miano wrote:
> >
> > That's in fact the real use case for the first two patches. Since bpf
> > tracepoints are still a rather common (and easy to use) troubleshooting and
> > monitoring tool why shouldn't we "enhance" their support with the newly
> > added map/prog IDs?
>
> because these tracepoints can be abused in the way that this patch demonstrated.
> Whether to keep this patch in the series or not is irrelevant.
I don't understand your abuse use-case, can you explain what you mean?
You do realize that these tracepoints can _only_ monitor the userspace
map activity (not kernel map changes) ... and we _do_ need a way to
debug this (and without the map_id I can tell which map).
--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
LinkedIn: http://www.linkedin.com/in/brouer
prev parent reply other threads:[~2018-04-23 20:22 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-18 15:30 [bpf-next PATCH 0/3] Add ID to bpf_map/prog tracepoints Sebastiano Miano
2018-04-18 15:30 ` [bpf-next PATCH 1/3] bpf: add id to map tracepoint Sebastiano Miano
2018-04-19 9:08 ` Jesper Dangaard Brouer
2018-04-18 15:30 ` [bpf-next PATCH 2/3] bpf: add id to prog tracepoint Sebastiano Miano
2018-04-19 9:10 ` Jesper Dangaard Brouer
2018-04-18 15:30 ` [bpf-next PATCH 3/3] bpf: add sample program to trace map events Sebastiano Miano
2018-04-19 9:20 ` Jesper Dangaard Brouer
2018-04-20 0:27 ` Alexei Starovoitov
2018-04-20 9:47 ` Jesper Dangaard Brouer
2018-04-23 14:08 ` Sebastiano Miano
2018-04-23 20:08 ` Alexei Starovoitov
2018-04-23 20:22 ` Jesper Dangaard Brouer [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180423222238.2636bdc8@redhat.com \
--to=brouer@redhat.com \
--cc=alexei.starovoitov@gmail.com \
--cc=ast@kernel.org \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=fulvio.risso@polito.it \
--cc=mingo@redhat.com \
--cc=netdev@vger.kernel.org \
--cc=rostedt@goodmis.org \
--cc=sebastiano.miano@polito.it \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.