Re: [PATCH v2 03/35] clk: mediatek: mt7622: Fix memory leak on module removal

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] misc: commit message inaccuracy regarding apmixedsys memory leak
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commit d007de80a8548f3cad6c0b96d9c2662f93cc4b64
Author: Akari Tsuyukusa <akkun11.open@gmail.com>

    clk: mediatek: mt7622: Fix memory leak on module removal

This commit fixes module removal issues in mt7622-apmixedsys and mt7622-infracfg
by calling platform_set_drvdata() in probe to ensure drvdata is available.

>     clk-mt7622-apmixedsys.c and clk-mt7622-infracfg.c do not call
>     platform_set_drvdata() during their driver probe callback,
>     but their remove callback calls platform_get_drvdata().
>     This results in platform_get_drvdata() returning NULL,
>     which leads to calling kfree(NULL) in mtk_free_clk_data(NULL).
>     This leaves clk_data unreleased, causing a memory leak.

[Severity: Medium]
Is this description completely accurate for clk-mt7622-apmixedsys.c?

While this is true for clk-mt7622-infracfg.c, clk-mt7622-apmixedsys.c uses
mtk_devm_alloc_clk_data() to allocate its clk_data, which means the memory
is automatically freed by the devres framework on unbind regardless of
drvdata. It never calls mtk_free_clk_data().

The actual consequence in clk_mt7622_apmixed_remove() is not a memory leak
of the clk_data structure itself, but rather a resource leak of the clocks
in the Common Clock Framework because the unregister functions return early
when passed a NULL clk_data pointer:

	mtk_clk_unregister_gates(apmixed_clks, ARRAY_SIZE(apmixed_clks), clk_data);
	mtk_clk_unregister_plls(plls, ARRAY_SIZE(plls), clk_data);

Could the commit message be updated to clarify that for apmixedsys, the
issue is a CCF resource leak rather than a memory leak from a missing kfree()?

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Sashiko AI review · https://sashiko.dev/#/patchset/20261013151734.3177690-1-akkun11.open@gmail.com?part=3