From: Zijun Hu quic_zijuhu@quicinc.com
For devm_phy_put(), its comment says it needs to invoke phy_put() to release the phy, but it will not actually invoke the function since devres_destroy() does not call devm_phy_release(), and the missing phy_put() call will cause:
- 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(); // leak refcount here
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@vger.kernel.org Cc: Lorenzo Pieralisi lpieralisi@kernel.org Cc: "Krzysztof Wilczyński" kw@linux.com Cc: Bjorn Helgaas bhelgaas@google.com Cc: "David S. Miller" davem@davemloft.net Cc: Eric Dumazet edumazet@google.com Cc: Jakub Kicinski kuba@kernel.org Cc: Paolo Abeni pabeni@redhat.com Cc: Johan Hovold johan@kernel.org Signed-off-by: Zijun Hu quic_zijuhu@quicinc.com --- drivers/phy/phy-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c index f053b525ccff..f190d7126613 100644 --- a/drivers/phy/phy-core.c +++ b/drivers/phy/phy-core.c @@ -737,7 +737,7 @@ void devm_phy_put(struct device *dev, struct phy *phy) if (!phy) return;
- r = devres_destroy(dev, devm_phy_release, devm_phy_match, phy); + r = devres_release(dev, devm_phy_release, devm_phy_match, phy); dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n"); } EXPORT_SYMBOL_GPL(devm_phy_put);