Le 20/12/2025 à 14:42, Haoxiang Li a écrit :
[Vous ne recevez pas souvent de courriers de [email protected].
Découvrez pourquoi ceci est important à
https://aka.ms/LearnAboutSenderIdentification ]
On Sat, 20 Dec 2025 11:45:10 +0100, Christophe Leroy wrote:
Your explanation is unclear. It is correct that put_device() is the
correct way to drop the device reference, and it is already what
rio_register_mport() does. Why do you need to move it out of
rio_register_mport() ? This is what you have to explain.
Sorry for the unclear changelog. I think if device_register() in
rio_register_mport() fails, put_device() is already called. Then,
the error path in fsl_rio_setup() also kfree() the port. I suspected
a potential double-free issue here, although I am unsure whether this
interpretation is correct.
The put_device() in rio_register_mport() releases the reference to
port->dev taken by device_register(). See the documentation in
https://elixir.bootlin.com/linux/v6.18/source/drivers/base/core.c#L3750
The kfree(port) in fsl_rio_setup() is to free the memory allocated by
the kzalloc() at
https://elixir.bootlin.com/linux/v6.18/source/arch/powerpc/sysdev/fsl_rio.c#L583
Those are two independant things.
AI code review or human code review ?
Human review.
Why do you remove this kfree() ? By doing this you will leak the port
pointer allocated earlier in the loop by kzalloc()
I just thought after device_register(), the cleanup should be done by
put_device().
You are talking about the cleanup of port->dev. Once you have cleaned up
port->dev you also have to cleanup port.
I would appreciate your clarification.
See above.
I might be wrong but from my point of view the existing code is correct.
Christophe
