From fe4bfa9b6d7bd752bfe4700c937f235aa8ce997b Mon Sep 17 00:00:00 2001 From: Zijun Hu Date: Fri, 13 Dec 2024 20:36:41 +0800 Subject: [PATCH] phy: core: Fix that API devm_phy_put() fails to release the phy MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Fix 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 Cc: Krzysztof Wilczyński Cc: Bjorn Helgaas Cc: David S. Miller Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Reviewed-by: Johan Hovold Signed-off-by: Zijun Hu Link: https://lore.kernel.org/r/20241213-phy_core_fix-v6-1-40ae28f5015a@quicinc.com Signed-off-by: Vinod Koul --- 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);