From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>
Date: Wed, 10 May 2023 22:00:20 +0200
Subject: [PATCH] net: fec: Better handle pm_runtime_get() failing in .remove()
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References: bsc#1012628
Patch-mainline: 6.3.4
Git-commit: f816b9829b19394d318e01953aa3b2721bca040d
[ Upstream commit f816b9829b19394d318e01953aa3b2721bca040d ]
In the (unlikely) event that pm_runtime_get() (disguised as
pm_runtime_resume_and_get()) fails, the remove callback returned an
error early. The problem with this is that the driver core ignores the
error value and continues removing the device. This results in a
resource leak. Worse the devm allocated resources are freed and so if a
callback of the driver is called later the register mapping is already
gone which probably results in a crash.
Fixes: a31eda65ba21 ("net: fec: fix clock count mis-match")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20230510200020.1534610-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/net/ethernet/freescale/fec_main.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 42ec6ca3..241df41d 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -4478,9 +4478,11 @@ fec_drv_remove(struct platform_device *pdev)
struct device_node *np = pdev->dev.of_node;
int ret;
- ret = pm_runtime_resume_and_get(&pdev->dev);
+ ret = pm_runtime_get_sync(&pdev->dev);
if (ret < 0)
- return ret;
+ dev_err(&pdev->dev,
+ "Failed to resume device in remove callback (%pe)\n",
+ ERR_PTR(ret));
cancel_work_sync(&fep->tx_timeout_work);
fec_ptp_stop(pdev);
@@ -4493,8 +4495,13 @@ fec_drv_remove(struct platform_device *pdev)
of_phy_deregister_fixed_link(np);
of_node_put(fep->phy_node);
- clk_disable_unprepare(fep->clk_ahb);
- clk_disable_unprepare(fep->clk_ipg);
+ /* After pm_runtime_get_sync() failed, the clks are still off, so skip
+ * disabling them again.
+ */
+ if (ret >= 0) {
+ clk_disable_unprepare(fep->clk_ahb);
+ clk_disable_unprepare(fep->clk_ipg);
+ }
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_disable(&pdev->dev);
--
2.35.3