igc: don't fail igc_probe() on LED setup error

Kohei Enju · NipaLocal · commit bcf47c1e3ec6 · 2025-09-17T08:00:58.000-07:00
When igc_led_setup() fails, igc_probe() fails and triggers kernel panic in free_netdev() since unregister_netdev() is not called. [1] This behavior can be tested using fault-injection framework, especially the failslab feature. [2] Since LED support is not mandatory, treat LED setup failures as non-fatal and continue probe with a warning message, consequently avoiding the kernel panic. [1] kernel BUG at net/core/dev.c:12047! Oops: invalid opcode: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 937 Comm: repro-igc-led-e Not tainted 6.17.0-rc4-enjuk-tnguy-00865-gc4940196ab02 torvalds#64 PREEMPT(voluntary) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:free_netdev+0x278/0x2b0 [...] Call Trace: <TASK> igc_probe+0x370/0x910 local_pci_probe+0x3a/0x80 pci_device_probe+0xd1/0x200 [...] [2] #!/bin/bash -ex FAILSLAB_PATH=/sys/kernel/debug/failslab/ DEVICE=0000:00:05.0 START_ADDR=$(grep " igc_led_setup" /proc/kallsyms \ | awk '{printf("0x%s", $1)}') END_ADDR=$(printf "0x%x" $((START_ADDR + 0x100))) echo $START_ADDR > $FAILSLAB_PATH/require-start echo $END_ADDR > $FAILSLAB_PATH/require-end echo 1 > $FAILSLAB_PATH/times echo 100 > $FAILSLAB_PATH/probability echo N > $FAILSLAB_PATH/ignore-gfp-wait echo $DEVICE > /sys/bus/pci/drivers/igc/bind Fixes: ea57870 ("igc: Add support for LEDs on i225/i226") Signed-off-by: Kohei Enju <enjuk@amazon.com> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Reviewed-by: Vitaly Lifshits <vitaly.lifshits@intel.com> Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> Tested-by: Mor Bar-Gabay <morx.bar.gabay@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> Signed-off-by: NipaLocal <nipa@local>
diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h
@@ -345,6 +345,7 @@ struct igc_adapter {
 	/* LEDs */
 	struct mutex led_mutex;
 	struct igc_led_classdev *leds;
+	bool leds_available;
 };
 
 void igc_up(struct igc_adapter *adapter);
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -7335,8 +7335,14 @@ static int igc_probe(struct pci_dev *pdev,
 
 	if (IS_ENABLED(CONFIG_IGC_LEDS)) {
 		err = igc_led_setup(adapter);
-		if (err)
-			goto err_register;
+		if (err) {
+			netdev_warn_once(netdev,
+					 "LED init failed (%d); continuing without LED support\n",
+					 err);
+			adapter->leds_available = false;
+		} else {
+			adapter->leds_available = true;
+		}
 	}
 
 	return 0;
@@ -7392,7 +7398,7 @@ static void igc_remove(struct pci_dev *pdev)
 	cancel_work_sync(&adapter->watchdog_task);
 	hrtimer_cancel(&adapter->hrtimer);
 
-	if (IS_ENABLED(CONFIG_IGC_LEDS))
+	if (IS_ENABLED(CONFIG_IGC_LEDS) && adapter->leds_available)
 		igc_led_free(adapter);
 
 	/* Release control of h/w to f/w.  If f/w is AMT enabled, this
