From c04d1b9ecce565455652ac3c6b17043cd475cf47 Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Mon, 22 Apr 2024 13:45:02 -0700 Subject: igc: Fix LED-related deadlock on driver unbind MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Roman reports a deadlock on unplug of a Thunderbolt docking station containing an Intel I225 Ethernet adapter. The root cause is that led_classdev's for LEDs on the adapter are registered such that they're device-managed by the netdev. That results in recursive acquisition of the rtnl_lock() mutex on unplug: When the driver calls unregister_netdev(), it acquires rtnl_lock(), then frees the device-managed resources. Upon unregistering the LEDs, netdev_trig_deactivate() invokes unregister_netdevice_notifier(), which tries to acquire rtnl_lock() again. Avoid by using non-device-managed LED registration. Stack trace for posterity: schedule+0x6e/0xf0 schedule_preempt_disabled+0x15/0x20 __mutex_lock+0x2a0/0x750 unregister_netdevice_notifier+0x40/0x150 netdev_trig_deactivate+0x1f/0x60 [ledtrig_netdev] led_trigger_set+0x102/0x330 led_classdev_unregister+0x4b/0x110 release_nodes+0x3d/0xb0 devres_release_all+0x8b/0xc0 device_del+0x34f/0x3c0 unregister_netdevice_many_notify+0x80b/0xaf0 unregister_netdev+0x7c/0xd0 igc_remove+0xd8/0x1e0 [igc] pci_device_remove+0x3f/0xb0 Fixes: ea578703b03d ("igc: Add support for LEDs on i225/i226") Reported-by: Roman Lozko Closes: https://lore.kernel.org/r/CAEhC_B=ksywxCG_+aQqXUrGEgKq+4mqnSV8EBHOKbC3-Obj9+Q@mail.gmail.com/ Reported-by: "Marek Marczykowski-Górecki" Closes: https://lore.kernel.org/r/ZhRD3cOtz5i-61PB@mail-itl/ Signed-off-by: Kurt Kanzenbach Signed-off-by: Lukas Wunner Cc: Heiner Kallweit Reviewed-by: Simon Horman Reviewed-by: Kurt Kanzenbach Tested-by: Kurt Kanzenbach # Intel i225 Tested-by: Naama Meir Signed-off-by: Tony Nguyen Link: https://lore.kernel.org/r/20240422204503.225448-1-anthony.l.nguyen@intel.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/intel/igc/igc_main.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/net/ethernet/intel/igc/igc_main.c') diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c index 35ad40a803cb..4d975d620a8e 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -7021,6 +7021,9 @@ static void igc_remove(struct pci_dev *pdev) cancel_work_sync(&adapter->watchdog_task); hrtimer_cancel(&adapter->hrtimer); + if (IS_ENABLED(CONFIG_IGC_LEDS)) + igc_led_free(adapter); + /* Release control of h/w to f/w. If f/w is AMT enabled, this * would have already happened in close and is redundant. */ -- cgit