On Thu, Oct 24, 2024 at 10:39:26PM +0800, Zijun Hu wrote:
> From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
>
> For devm_phy_put(), its comment says it needs to invoke phy_put() to
> release the phy, but it does not invoke the function actually since
> devres_destroy() will not call devm_phy_release() at all which will
> call the function, and the missing phy_put() call will cause:
Please split the above up in at least two sentences to make it easier to
parse. Split it after devm_phy_release() and rephrase the latter part
(e.g. by dropping "at all which will call the function").
> - The phy fails to be released.
> - devm_phy_put() can not fully undo what API devm_phy_get() does.
> - Leak refcount of both the module and device for below typical usage:
>
> devm_phy_get(); // or its variant
> ...
> err = do_something();
> if (err)
> goto err_out;
> ...
> err_out:
> devm_phy_put();
>
> The file(s) affected by this issue are shown below since they have such
> typical usage.
> drivers/pci/controller/cadence/pcie-cadence.c
> drivers/net/ethernet/ti/am65-cpsw-nuss.c
>
> Fixed by using devres_release() instead of devres_destroy() within the API
>
> Fixes: ff764963479a ("drivers: phy: add generic PHY framework")
> Cc: stable@xxxxxxxxxxxxxxx
> Cc: Lorenzo Pieralisi <lpieralisi@xxxxxxxxxx>
> Cc: "Krzysztof Wilczyński" <kw@xxxxxxxxx>
> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
> Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> Cc: Paolo Abeni <pabeni@xxxxxxxxxx>
> Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
Diff itself looks good. Nice find.
Johan
