git.openwrt.org Git - openwrt/openwrt.git/blob

   1 From 19fa4f2a85d777a8052e869c1b892a2f7556569d Mon Sep 17 00:00:00 2001
   2 From: Heiner Kallweit <hkallweit1@gmail.com>
   3 Date: Mon, 8 Apr 2024 20:47:40 +0200
   4 Subject: [PATCH] r8169: fix LED-related deadlock on module removal
   5
   6 Binding devm_led_classdev_register() to the netdev is problematic
   7 because on module removal we get a RTNL-related deadlock. Fix this
   8 by avoiding the device-managed LED functions.
   9
  10 Note: We can safely call led_classdev_unregister() for a LED even
  11 if registering it failed, because led_classdev_unregister() detects
  12 this and is a no-op in this case.
  13
  14 Fixes: 18764b883e15 ("r8169: add support for LED's on RTL8168/RTL8101")
  15 Cc: stable@vger.kernel.org
  16 Reported-by: Lukas Wunner <lukas@wunner.de>
  17 Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
  18 Reviewed-by: Andrew Lunn <andrew@lunn.ch>
  19 Signed-off-by: David S. Miller <davem@davemloft.net>
  20 ---
  21  drivers/net/ethernet/realtek/r8169.h      |  6 ++--
  22  drivers/net/ethernet/realtek/r8169_leds.c | 35 +++++++++++++++--------
  23  drivers/net/ethernet/realtek/r8169_main.c |  8 ++++--
  24  3 files changed, 33 insertions(+), 16 deletions(-)
  25
  26 --- a/drivers/net/ethernet/realtek/r8169.h
  27 +++ b/drivers/net/ethernet/realtek/r8169.h
  28 @@ -73,6 +73,7 @@ enum mac_version {
  29  };
  30
  31  struct rtl8169_private;
  32 +struct r8169_led_classdev;
  33
  34  void r8169_apply_firmware(struct rtl8169_private *tp);
  35  u16 rtl8168h_2_get_adc_bias_ioffset(struct rtl8169_private *tp);
  36 @@ -84,7 +85,8 @@ void r8169_get_led_name(struct rtl8169_p
  37                         char *buf, int buf_len);
  38  int rtl8168_get_led_mode(struct rtl8169_private *tp);
  39  int rtl8168_led_mod_ctrl(struct rtl8169_private *tp, u16 mask, u16 val);
  40 -void rtl8168_init_leds(struct net_device *ndev);
  41 +struct r8169_led_classdev *rtl8168_init_leds(struct net_device *ndev);
  42  int rtl8125_get_led_mode(struct rtl8169_private *tp, int index);
  43  int rtl8125_set_led_mode(struct rtl8169_private *tp, int index, u16 mode);
  44 -void rtl8125_init_leds(struct net_device *ndev);
  45 +struct r8169_led_classdev *rtl8125_init_leds(struct net_device *ndev);
  46 +void r8169_remove_leds(struct r8169_led_classdev *leds);
  47 --- a/drivers/net/ethernet/realtek/r8169_leds.c
  48 +++ b/drivers/net/ethernet/realtek/r8169_leds.c
  49 @@ -147,22 +147,22 @@ static void rtl8168_setup_ldev(struct r8
  50         led_cdev->hw_control_get_device = r8169_led_hw_control_get_device;
  51
  52         /* ignore errors */
  53 -       devm_led_classdev_register(&ndev->dev, led_cdev);
  54 +       led_classdev_register(&ndev->dev, led_cdev);
  55  }
  56
  57 -void rtl8168_init_leds(struct net_device *ndev)
  58 +struct r8169_led_classdev *rtl8168_init_leds(struct net_device *ndev)
  59  {
  60 -       /* bind resource mgmt to netdev */
  61 -       struct device *dev = &ndev->dev;
  62         struct r8169_led_classdev *leds;
  63         int i;
  64
  65 -       leds = devm_kcalloc(dev, RTL8168_NUM_LEDS, sizeof(*leds), GFP_KERNEL);
  66 +       leds = kcalloc(RTL8168_NUM_LEDS + 1, sizeof(*leds), GFP_KERNEL);
  67         if (!leds)
  68 -               return;
  69 +               return NULL;
  70
  71         for (i = 0; i < RTL8168_NUM_LEDS; i++)
  72                 rtl8168_setup_ldev(leds + i, ndev, i);
  73 +
  74 +       return leds;
  75  }
  76
  77  static int rtl8125_led_hw_control_is_supported(struct led_classdev *led_cdev,
  78 @@ -246,20 +246,31 @@ static void rtl8125_setup_led_ldev(struc
  79         led_cdev->hw_control_get_device = r8169_led_hw_control_get_device;
  80
  81         /* ignore errors */
  82 -       devm_led_classdev_register(&ndev->dev, led_cdev);
  83 +       led_classdev_register(&ndev->dev, led_cdev);
  84  }
  85
  86 -void rtl8125_init_leds(struct net_device *ndev)
  87 +struct r8169_led_classdev *rtl8125_init_leds(struct net_device *ndev)
  88  {
  89 -       /* bind resource mgmt to netdev */
  90 -       struct device *dev = &ndev->dev;
  91         struct r8169_led_classdev *leds;
  92         int i;
  93
  94 -       leds = devm_kcalloc(dev, RTL8125_NUM_LEDS, sizeof(*leds), GFP_KERNEL);
  95 +       leds = kcalloc(RTL8125_NUM_LEDS + 1, sizeof(*leds), GFP_KERNEL);
  96         if (!leds)
  97 -               return;
  98 +               return NULL;
  99
 100         for (i = 0; i < RTL8125_NUM_LEDS; i++)
 101                 rtl8125_setup_led_ldev(leds + i, ndev, i);
 102 +
 103 +       return leds;
 104 +}
 105 +
 106 +void r8169_remove_leds(struct r8169_led_classdev *leds)
 107 +{
 108 +       if (!leds)
 109 +               return;
 110 +
 111 +       for (struct r8169_led_classdev *l = leds; l->ndev; l++)
 112 +               led_classdev_unregister(&l->led);
 113 +
 114 +       kfree(leds);
 115  }
 116 --- a/drivers/net/ethernet/realtek/r8169_main.c
 117 +++ b/drivers/net/ethernet/realtek/r8169_main.c
 118 @@ -674,6 +674,8 @@ struct rtl8169_private {
 119         const char *fw_name;
 120         struct rtl_fw *rtl_fw;
 121
 122 +       struct r8169_led_classdev *leds;
 123 +
 124         u32 ocp_base;
 125  };
 126
 127 @@ -5067,6 +5069,8 @@ static void rtl_remove_one(struct pci_de
 128
 129         cancel_work_sync(&tp->wk.work);
 130
 131 +       r8169_remove_leds(tp->leds);
 132 +
 133         unregister_netdev(tp->dev);
 134
 135         if (tp->dash_type != RTL_DASH_NONE)
 136 @@ -5525,9 +5529,9 @@ static int rtl_init_one(struct pci_dev *
 137
 138         if (IS_ENABLED(CONFIG_R8169_LEDS)) {
 139                 if (rtl_is_8125(tp))
 140 -                       rtl8125_init_leds(dev);
 141 +                       tp->leds = rtl8125_init_leds(dev);
 142                 else if (tp->mac_version > RTL_GIGA_MAC_VER_06)
 143 -                       rtl8168_init_leds(dev);
 144 +                       tp->leds = rtl8168_init_leds(dev);
 145         }
 146
 147         netdev_info(dev, "%s, %pM, XID %03x, IRQ %d\n",