All of lore.kernel.org
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: KP Singh <kpsingh@kernel.org>
Cc: Chris Mason <clm@meta.com>, Steven Rostedt <rostedt@goodmis.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Florent Revest <revest@chromium.org>, bpf <bpf@vger.kernel.org>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Andrii Nakryiko <andrii@kernel.org>,
	Brendan Jackman <jackmanb@google.com>,
	markowsky@google.com, Masami Hiramatsu <mhiramat@kernel.org>,
	Xu Kuohai <xukuohai@huawei.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Christoph Hellwig <hch@infradead.org>
Subject: Re: [RFC 0/1] BPF tracing for arm64 using fprobe
Date: Mon, 21 Nov 2022 15:16:54 +0100	[thread overview]
Message-ID: <Y3uIVknDWTS0bMTT@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <CACYkzJ613nhXViBpDuGWeEWzjfSJjbB1=KNpYtNDC6Xn7yizbw@mail.gmail.com>

On Mon, Nov 21, 2022 at 02:47:10PM +0100, KP Singh wrote:

> > > How do I know that a function return was modified by BPF? If I'm debugging
> 
> You can list the BPF programs that are loaded in the kernel with
> 
> # bpftool prog list

Only when you have access to the machine; most cases it's people sending
random splats by email.

> Also, the BPF programs show up in call stacks when you are debugging.

Only when it splats inside the BPF part, not when it splats after
because BPF changed semantics of a function.



  reply	other threads:[~2022-11-21 14:17 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-08 22:06 [RFC 0/1] BPF tracing for arm64 using fprobe Florent Revest
2022-11-08 22:06 ` [RFC 1/1] bpf: Invoke tracing progs using fprobe on archs without direct call Florent Revest
2022-11-17  2:41 ` [RFC 0/1] BPF tracing for arm64 using fprobe Alexei Starovoitov
2022-11-17 13:33   ` Masami Hiramatsu
2022-11-17 16:50     ` Alexei Starovoitov
2022-11-18 16:26       ` Mark Rutland
2022-11-17 17:16   ` Steven Rostedt
2022-11-17 21:55     ` Chris Mason
2022-11-17 22:40       ` Steven Rostedt
2022-11-18 16:34         ` Mark Rutland
2022-11-18 16:45           ` Steven Rostedt
2022-11-18 17:44             ` Chris Mason
2022-11-18 18:06               ` Steven Rostedt
2022-11-18 18:52                 ` Chris Mason
2022-11-21 13:47                   ` KP Singh
2022-11-21 14:16                     ` Peter Zijlstra [this message]
2022-11-21 14:23                       ` KP Singh
2022-11-21 15:15                     ` Steven Rostedt
2022-11-21 15:29                       ` KP Singh
2022-11-21 15:39                         ` Steven Rostedt
2022-11-21 16:16                         ` Jiri Kosina
2022-11-21 15:40                       ` Alexei Starovoitov
2022-11-21 15:45                         ` Steven Rostedt
2022-11-21 15:55                           ` Borislav Petkov
2022-11-21 10:09                 ` Peter Zijlstra
2022-11-21 14:40                   ` Masami Hiramatsu
2022-11-18 16:18       ` Mark Rutland
2022-11-17 13:16 ` Masami Hiramatsu

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=Y3uIVknDWTS0bMTT@hirez.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=alexei.starovoitov@gmail.com \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=clm@meta.com \
    --cc=daniel@iogearbox.net \
    --cc=gregkh@linuxfoundation.org \
    --cc=hch@infradead.org \
    --cc=jackmanb@google.com \
    --cc=kpsingh@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=markowsky@google.com \
    --cc=mhiramat@kernel.org \
    --cc=revest@chromium.org \
    --cc=rostedt@goodmis.org \
    --cc=torvalds@linux-foundation.org \
    --cc=xukuohai@huawei.com \
    /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.