Re: [PATCH v2] clk: eyeq: fix memory leak in eqc_auxdev_create() error path

["Théo Lebrun" <theo.lebrun@bootlin.com>]

Hello Guangshuo,

Subject is:

> Subject: [PATCH v2] clk: eyeq: fix memory leak in eqc_auxdev_create()
>          error path

I cannot find a public V1?
https://lore.kernel.org/lkml/?q=s%3Aeyeq+f%3AGuangshuo

On Sun Apr 12, 2026 at 2:42 PM CEST, Guangshuo Li wrote:
> eqc_auxdev_create() allocates an auxiliary_device with kzalloc() before
> calling auxiliary_device_init().
>
> When auxiliary_device_init() returns an error, the function exits
> without freeing adev. Since the release callback is only expected to
> handle cleanup after successful initialization, adev should be freed
> explicitly in this path.
>
> Add the missing kfree(adev) before returning from the
> auxiliary_device_init() error path.
>
> Fixes: 25d904946a0b ("clk: eyeq: add driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>

I have a guess this is LLM generated?
Are you missing the Assisted-by trailer?
https://docs.kernel.org/process/coding-assistants.html#attribution

The patch could be in theory useful.
In practice however, it's a different story.

 - Comit message says "Since the release callback is only expected to
   handle cleanup after successful initialization, adev should be freed
   explicitly in this path".

   Two things are wrong here:

   1. the driver cannot be removed so there is no "release
      callback" (guessing you mean driver remove?).

   2. this text seems to imply eqc_auxdev_create() makes probe fail,
      which it doesn't. It only generates a warning and keeps probing.

 - This driver cannot be built as module (will always be probed at boot)
   and cannot be removed. So the "leak" we are talking about is
   2 * sizeof(struct auxiliary_device)

   But in no sensible case it can occur. The platforms that use this
   driver probably cannot boot if our auxiliary drivers aren't present.
   So if eqc_auxdev_create() fails then the warning is here to be nice
   but you probably will fail booting afterwards.

   My guess is: you might succeed booting without the reset driver but
   if you fail the pinctrl one then you won't have a UART. Anyway in no
   world do you have a sensible EyeQ kernel config that leads to
   clk-eyeq probing but not its auxdevs.

 - If you fix this then there are other resources cleanup to "fix".

    - ioremap() in eqc_probe()
    - kzalloc of cells in eqc_probe()
    - probably others

   But, same as above, "fixing" those will only be useful in kernels
   that will panic in a few milliseconds.

Thanks,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com