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Date:   Tue, 26 Jan 2021 21:20:59 +0100
From:   Oleg Nesterov <oleg@redhat.com>
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Steven Rostedt <rostedt@goodmis.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
Message-ID: <20210126202058.GC12469@redhat.com>
References: <20210125160108.2147511-1-Jianlin.Lv@arm.com>
 <20210125181926.GA10248@redhat.com>
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On 01/26, Masami Hiramatsu wrote:
>
> > >
> > > IOW, the "offset != 0" check removed by this patch is obviously wrong, right?
> > >
>
> 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 ?

Oleg.