From 19fa4f2a85d777a8052e869c1b892a2f7556569d Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Mon, 8 Apr 2024 20:47:40 +0200 Subject: [PATCH] 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 Signed-off-by: Heiner Kallweit Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- drivers/net/ethernet/realtek/r8169.h | 6 ++-- drivers/net/ethernet/realtek/r8169_leds.c | 35 +++++++++++++++-------- drivers/net/ethernet/realtek/r8169_main.c | 8 ++++-- 3 files changed, 33 insertions(+), 16 deletions(-) --- 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_p 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); --- a/drivers/net/ethernet/realtek/r8169_leds.c +++ b/drivers/net/ethernet/realtek/r8169_leds.c @@ -147,22 +147,22 @@ static void rtl8168_setup_ldev(struct r8 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, @@ -246,20 +246,31 @@ static void rtl8125_setup_led_ldev(struc 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); } --- 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; }; @@ -5040,6 +5042,8 @@ static void rtl_remove_one(struct pci_de cancel_work_sync(&tp->wk.work); + r8169_remove_leds(tp->leds); + unregister_netdev(tp->dev); if (tp->dash_type != RTL_DASH_NONE) @@ -5498,9 +5502,9 @@ static int rtl_init_one(struct pci_dev * 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",