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From: Nam Cao <namcao@linutronix.de>
To: naveen@kernel.org, anil.s.keshavamurthy@intel.com, davem@davemloft.net,
	mhiramat@kernel.org, linux-kernel@vger.kernel.org,
	linux-trace-kernel@vger.kernel.org
Cc: john.ogness@linutronix.de
Subject: kprobe on local function
Message-ID: <20250122075939.qw7HsuMd@linutronix.de>
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Hi,

I installed a kretprobe on the function "rt_mutex_slowunlock". Although the
function is called, the probe is never hit.

The reason is because there are 3 copies of rt_mutex_slowunlock() in
vmlinux (at least for x86 defconfig + CONFIG_PREEMPT_RT). But probe point
is only installed in 1 copy.

Is this considered a bug? Or is kprobe not intended to be used for local
function? Should we modify kprobe to support such cases?

Best regards,
Nam