From: Steven Rostedt <rostedt@goodmis.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>,
Jianlin Lv <Jianlin.Lv@arm.com>,
mingo@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] tracing: precise log info for kretprobe addr err
Date: Tue, 26 Jan 2021 15:43:02 -0500 [thread overview]
Message-ID: <20210126154302.302a3bb0@gandalf.local.home> (raw)
In-Reply-To: <20210126202058.GC12469@redhat.com>
On Tue, 26 Jan 2021 21:20:59 +0100
Oleg Nesterov <oleg@redhat.com> wrote:
> > No, not wrong. Even offset != 0, if the symbol exists in the kernel,
> > kprobe_on_func_entry() will check it.
>
> Yes, but unless I am totally confused... if kprobe_on_func_entry() returns false,
> then trace_kprobe_create() should fail with BAD_RETPROBE even if offset == 0 ?
From what I understand. kprobe_on_func_entry() can return false if you pass
in: "MOD:not_yet_loaded_module_func", but this is OK, because when the
module is loaded, and the "not_yet_loaded_module_func" exists, the
kretprobe will then be added.
The strchr(symbol,":") check is to see if "MOD:" (or some other ":" command)
is in the name, and we don't want it to fail if it is. Which is why we
should have that commented.
-- Steve
next prev parent reply other threads:[~2021-01-27 3:21 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-25 16:01 [PATCH v3] tracing: precise log info for kretprobe addr err Jianlin Lv
2021-01-25 18:19 ` Oleg Nesterov
2021-01-25 18:38 ` Steven Rostedt
2021-01-26 4:15 ` Masami Hiramatsu
2021-01-26 10:02 ` Jianlin Lv
2021-01-26 20:20 ` Oleg Nesterov
2021-01-26 20:43 ` Steven Rostedt [this message]
2021-01-26 21:17 ` Oleg Nesterov
2021-01-26 21:40 ` Steven Rostedt
2021-01-27 2:14 ` Masami Hiramatsu
2021-01-27 2:02 ` Masami Hiramatsu
2021-01-27 2:46 ` Jianlin Lv
2021-01-27 13:27 ` Masami Hiramatsu
2021-01-27 14:25 ` Jianlin Lv
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=20210126154302.302a3bb0@gandalf.local.home \
--to=rostedt@goodmis.org \
--cc=Jianlin.Lv@arm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mhiramat@kernel.org \
--cc=mingo@redhat.com \
--cc=oleg@redhat.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).