[PATCH] net: wan: fsl_ucc_hdlc: release the net device on remove

[PATCH] net: wan: fsl_ucc_hdlc: release the net device on remove

[Wentao Liang]

ucc_hdlc_probe() allocates the net device with alloc_hdlcdev() and
registers it with register_hdlc_device(), but ucc_hdlc_remove() only
tears down the QE resources and frees the private data.  The net device
is never unregistered or freed, so after the platform device is removed
or the module is unloaded it stays registered, keeps its reference to
the module and is left pointing at the freed private data.

Unregister and free the net device in ucc_hdlc_remove(), before the
private data is released, as fsl_qmc_hdlc does.

Fixes: c19b6d246a35 ("drivers/net: support hdlc function for QE-UCC")
Cc: stable@vger.kernel.org
Assisted-by: DeepSeek-V4.1-Flash and OpenAI Codex
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/net/wan/fsl_ucc_hdlc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
index 809f21fb93f5..f815cac82518 100644
--- a/drivers/net/wan/fsl_ucc_hdlc.c
+++ b/drivers/net/wan/fsl_ucc_hdlc.c
@@ -1255,6 +1255,7 @@ static void ucc_hdlc_remove(struct platform_device *pdev)
 {
 	struct ucc_hdlc_private *priv = dev_get_drvdata(&pdev->dev);
 
+	unregister_hdlc_device(priv->ndev);
 	uhdlc_memclean(priv);
 
 	if (priv->utdm && priv->utdm->si_regs) {
@@ -1266,6 +1267,7 @@ static void ucc_hdlc_remove(struct platform_device *pdev)
 		iounmap(priv->utdm->siram);
 		priv->utdm->siram = NULL;
 	}
+	free_netdev(priv->ndev);
 	kfree(priv);
 
 	dev_info(&pdev->dev, "UCC based hdlc module removed\n");
-- 
2.34.1

Re: [PATCH] net: wan: fsl_ucc_hdlc: release the net device on remove

[netdev-bot+sinfo]

Hi!

This is an automated message. This series looks like a fix, but its
commit messages seem to be missing some information:

 - How the issue was discovered, e.g. hit in production, hit during
   development, syzbot report, manual code inspection, LLM or static
   analysis tool scan.

 - Whether the issue was actually triggered, or is only theoretical
   (e.g. found by code inspection). If it was triggered please include
   the symptoms, like the stack trace or error messages.

Please do not repost the series just to address the above. Instead,
reply to this email with the missing information, so that reviewers
can take it into account. If the series needs another revision for
other reasons, please include the information in the commit messages
then.

The evaluation is done by an LLM so it may be wrong, if you think
that is the case please reply and explain.

Re: [PATCH] net: wan: fsl_ucc_hdlc: release the net device on remove

[Krzysztof Kozlowski]

On Tue, 03 Nov 2026 10:42:37 +0000, Wentao Liang wrote:
> ucc_hdlc_probe() allocates the net device with alloc_hdlcdev() and
> registers it with register_hdlc_device(), but ucc_hdlc_remove() only
> tears down the QE resources and frees the private data.  The net device
> is never unregistered or freed, so after the platform device is removed
> or the module is unloaded it stays registered, keeps its reference to
> the module and is left pointing at the freed private data.
> 
> Unregister and free the net device in ucc_hdlc_remove(), before the
> private data is released, as fsl_qmc_hdlc does.
> 
> Fixes: c19b6d246a35 ("drivers/net: support hdlc function for QE-UCC")
> Cc: stable@vger.kernel.org
> Assisted-by: DeepSeek-V4.1-Flash and OpenAI Codex
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
> ---
>  drivers/net/wan/fsl_ucc_hdlc.c | 2 ++
>  1 file changed, 2 insertions(+)
> 

Multiple things here:
1. Your team ignored completely previous feedback. Multiple times.

2. You use multiple identities with this email address, thus I doubt that we
   speak with an actual person.

3. Your bot does not even bother running checkpatch, right?

4. Nothing of this was reproduced nor tested.

5. Finally, the same feedback:
You sent multiple independent patches, to multiple independent
subsystems. The amount of these patches clearly suggest this was
AI generated and most likely not tested.

More importantly, you sent all this work without properly organizing
relevant patches into patchsets. This makes reviewing difficult
and might cause multiple reviewers to address the same issue.
Replying to the entire set is impossible and requires handling each
patch independently, instead of applying or discarding the set.
Maintainers also won't see the bigger picture of your work. Quite
worrying.

This is on the verge of hostile patch: bomb us with so many
contributions, we won't be able to handle them in efficient manner,
like responding ONCE to ask you to slow down.  Considering all this
is untested and LLM generated, I have even more doubts whether this
should be considered for review.

Please read kernel documentation BEFORE posting more work. It will
explain you how to identify subsystems, how to organize your work per
subsystem (so a patchset grouping multiple patches with a short cover
letter), how to document the issue discovery method and what was
or was not tested.

Best regards,
Krzysztof