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From: Nam Cao <namcao@linutronix.de>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Gabriele Monaco <gmonaco@redhat.com>,
	linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Subject: Re: [PATCH] rv: Ensure containers are registered first
Message-ID: <20250718104018.lyupqBnR@linutronix.de>
References: <20250718091850.2057864-1-namcao@linutronix.de>
 <2025071835-enjoying-darn-f5d8@gregkh>
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In-Reply-To: <2025071835-enjoying-darn-f5d8@gregkh>

On Fri, Jul 18, 2025 at 12:27:14PM +0200, Greg KH wrote:
> On Fri, Jul 18, 2025 at 11:18:50AM +0200, Nam Cao wrote:
> > If rv_register_monitor() is called with a non-NULL parent pointer (i.e. by
> > monitors inside a container), it is expected that the parent (a.k.a
> > container) is already registered.
> > 
> > The containers seem to always be registered first. I suspect because of the
> > order in Makefile. But nothing guarantees this.
> 
> Yes, linking order matters, and it does guarantee this.  We rely on
> linking order in the kernel in many places.

Hmm, I thought this is just how the linker happens to behave, but not a
guarantee.

Let's discard this patch then.

Nam