On 10/09/2025 16:47, Kohei Enju wrote:
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 #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]> Reviewed-by: Paul Menzel <[email protected]> Reviewed-by: Aleksandr Loktionov <[email protected]> Reviewed-by: Vitaly Lifshits <[email protected]> Reviewed-by: Kurt Kanzenbach <[email protected]> --- Changes: v1->v2: - don't fail probe when led setup fails - rephrase subject and commit message v1: https://lore.kernel.org/intel-wired-lan/[email protected]/ --- drivers/net/ethernet/intel/igc/igc.h | 1 + drivers/net/ethernet/intel/igc/igc_main.c | 12 +++++++++--- 2 files changed, 10 insertions(+), 3 deletions(-)
Tested-by: Mor Bar-Gabay <[email protected]>
