r8169: fix LED-related deadlock on module removal

Binding devm_led_classdev_register() to the netdev is problematic
because on module removal we get a RTNL-related deadlock. Fix this
by avoiding the device-managed LED functions.

Note: We can safely call led_classdev_unregister() for a LED even
if registering it failed, because led_classdev_unregister() detects
this and is a no-op in this case.

Fixes: 18764b883e15 ("r8169: add support for LED's on RTL8168/RTL8101")
Cc: stable@vger.kernel.org
Reported-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/realtek/r8169.h b/drivers/net/ethernet/realtek/r8169.h
index 4c043052198d470ce0a2f82dbe1f3be67b35c827..00882ffc7a029ef63c1c8605541f86339999e724 100644 (file)
--- a/drivers/net/ethernet/realtek/r8169.h
+++ b/drivers/net/ethernet/realtek/r8169.h
@@ -73,6 +73,7 @@ enum mac_version {
 };
 
 struct rtl8169_private;
+struct r8169_led_classdev;
 
 void r8169_apply_firmware(struct rtl8169_private *tp);
 u16 rtl8168h_2_get_adc_bias_ioffset(struct rtl8169_private *tp);
@@ -84,7 +85,8 @@ void r8169_get_led_name(struct rtl8169_private *tp, int idx,
                        char *buf, int buf_len);
 int rtl8168_get_led_mode(struct rtl8169_private *tp);
 int rtl8168_led_mod_ctrl(struct rtl8169_private *tp, u16 mask, u16 val);
-void rtl8168_init_leds(struct net_device *ndev);
+struct r8169_led_classdev *rtl8168_init_leds(struct net_device *ndev);
 int rtl8125_get_led_mode(struct rtl8169_private *tp, int index);
 int rtl8125_set_led_mode(struct rtl8169_private *tp, int index, u16 mode);
-void rtl8125_init_leds(struct net_device *ndev);
+struct r8169_led_classdev *rtl8125_init_leds(struct net_device *ndev);
+void r8169_remove_leds(struct r8169_led_classdev *leds);

diff --git a/drivers/net/ethernet/realtek/r8169_leds.c b/drivers/net/ethernet/realtek/r8169_leds.c
index 7c5dc9d0df855ef57592b7a25d4357232279a60f..e10bee706bc691b8c32ec2410baa8d4279de69a0 100644 (file)
--- a/drivers/net/ethernet/realtek/r8169_leds.c
+++ b/drivers/net/ethernet/realtek/r8169_leds.c
@@ -146,22 +146,22 @@ static void rtl8168_setup_ldev(struct r8169_led_classdev *ldev,
        led_cdev->hw_control_get_device = r8169_led_hw_control_get_device;
 
        /* ignore errors */
-       devm_led_classdev_register(&ndev->dev, led_cdev);
+       led_classdev_register(&ndev->dev, led_cdev);
 }
 
-void rtl8168_init_leds(struct net_device *ndev)
+struct r8169_led_classdev *rtl8168_init_leds(struct net_device *ndev)
 {
-       /* bind resource mgmt to netdev */
-       struct device *dev = &ndev->dev;
        struct r8169_led_classdev *leds;
        int i;
 
-       leds = devm_kcalloc(dev, RTL8168_NUM_LEDS, sizeof(*leds), GFP_KERNEL);
+       leds = kcalloc(RTL8168_NUM_LEDS + 1, sizeof(*leds), GFP_KERNEL);
        if (!leds)
-               return;
+               return NULL;
 
        for (i = 0; i < RTL8168_NUM_LEDS; i++)
                rtl8168_setup_ldev(leds + i, ndev, i);
+
+       return leds;
 }
 
 static int rtl8125_led_hw_control_is_supported(struct led_classdev *led_cdev,
@@ -245,20 +245,31 @@ static void rtl8125_setup_led_ldev(struct r8169_led_classdev *ldev,
        led_cdev->hw_control_get_device = r8169_led_hw_control_get_device;
 
        /* ignore errors */
-       devm_led_classdev_register(&ndev->dev, led_cdev);
+       led_classdev_register(&ndev->dev, led_cdev);
 }
 
-void rtl8125_init_leds(struct net_device *ndev)
+struct r8169_led_classdev *rtl8125_init_leds(struct net_device *ndev)
 {
-       /* bind resource mgmt to netdev */
-       struct device *dev = &ndev->dev;
        struct r8169_led_classdev *leds;
        int i;
 
-       leds = devm_kcalloc(dev, RTL8125_NUM_LEDS, sizeof(*leds), GFP_KERNEL);
+       leds = kcalloc(RTL8125_NUM_LEDS + 1, sizeof(*leds), GFP_KERNEL);
        if (!leds)
-               return;
+               return NULL;
 
        for (i = 0; i < RTL8125_NUM_LEDS; i++)
                rtl8125_setup_led_ldev(leds + i, ndev, i);
+
+       return leds;
+}
+
+void r8169_remove_leds(struct r8169_led_classdev *leds)
+{
+       if (!leds)
+               return;
+
+       for (struct r8169_led_classdev *l = leds; l->ndev; l++)
+               led_classdev_unregister(&l->led);
+
+       kfree(leds);
 }

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 6f1e6f386b7ba7277bc211765b8ef49d9fcd6750..8a27328eae34b7ef10b134d354e7ac0ccc032b28 100644 (file)
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -647,6 +647,8 @@ struct rtl8169_private {
        const char *fw_name;
        struct rtl_fw *rtl_fw;
 
+       struct r8169_led_classdev *leds;
+
        u32 ocp_base;
 };
 
@@ -5044,6 +5046,8 @@ static void rtl_remove_one(struct pci_dev *pdev)
 
        cancel_work_sync(&tp->wk.work);
 
+       r8169_remove_leds(tp->leds);
+
        unregister_netdev(tp->dev);
 
        if (tp->dash_type != RTL_DASH_NONE)
@@ -5501,9 +5505,9 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
        if (IS_ENABLED(CONFIG_R8169_LEDS)) {
                if (rtl_is_8125(tp))
-                       rtl8125_init_leds(dev);
+                       tp->leds = rtl8125_init_leds(dev);
                else if (tp->mac_version > RTL_GIGA_MAC_VER_06)
-                       rtl8168_init_leds(dev);
+                       tp->leds = rtl8168_init_leds(dev);
        }
 
        netdev_info(dev, "%s, %pM, XID %03x, IRQ %d\n",