> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf
> Of Kohei Enju
> Sent: Saturday, September 6, 2025 7:52 AM
> To: [email protected]; [email protected]
> Cc: Nguyen, Anthony L <[email protected]>; Kitszel,
> Przemyslaw <[email protected]>; Andrew Lunn
> <[email protected]>; David S. Miller <[email protected]>; Eric
> Dumazet <[email protected]>; Jakub Kicinski <[email protected]>; Paolo
> Abeni <[email protected]>; Kurt Kanzenbach <[email protected]>;
> [email protected]; Kohei Enju <[email protected]>
> Subject: [Intel-wired-lan] [PATCH v1 iwl-net] igc: unregister netdev
> when igc_led_setup() fails in igc_probe()
>
> Currently igc_probe() doesn't unregister netdev when igc_led_setup()
> fails, causing BUG_ON() in free_netdev() and then kernel panics. [1]
>
> This behavior can be tested using fault-injection framework. I used
> the failslab feature to test the issue. [2]
>
> Call unregister_netdev() when igc_led_setup() fails to avoid 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 #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: ea578703b03d ("igc: Add support for LEDs on i225/i226")
> Signed-off-by: Kohei Enju <[email protected]>
> ---
> drivers/net/ethernet/intel/igc/igc_main.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/intel/igc/igc_main.c
> b/drivers/net/ethernet/intel/igc/igc_main.c
> index e79b14d50b24..95c415d0917d 100644
> --- a/drivers/net/ethernet/intel/igc/igc_main.c
> +++ b/drivers/net/ethernet/intel/igc/igc_main.c
> @@ -7336,11 +7336,13 @@ static int igc_probe(struct pci_dev *pdev,
> if (IS_ENABLED(CONFIG_IGC_LEDS)) {
> err = igc_led_setup(adapter);
> if (err)
> - goto err_register;
> + goto err_led_setup;
> }
>
> return 0;
>
> +err_led_setup:
> + unregister_netdev(netdev);
> err_register:
> igc_release_hw_control(adapter);
> igc_ptp_stop(adapter);
> --
> 2.48.1
Reviewed-by: Aleksandr Loktionov <[email protected]>
