RE: ld.lld: error: undefined symbol: led_classdev_multicolor_unregister

From: Ping-Ke Shih

Date: Thu Sep 17 2026 - 22:28:36 EST


kernel test robot <lkp@xxxxxxxxx> wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: b5a051f6b840d48f159166ef073d3021989bfb50
> commit: 721d90c8509aee195c3714b70c4cff612fbb3a1c wifi: rtw89: add multicolor LED support for RTL8852CU
> valve board
> date: 8 weeks ago
> config: hexagon-randconfig-r072-20260915
> (https://download.01.org/0day-ci/archive/20260917/202609172315.ZYoKvKBS-lkp@xxxxxxxxx/config)
> compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project
> 6009708b4367171ccdbf4b5905cb6a803753fe18)
> smatch: v0.5.0-9187-g5189e3fb
> reproduce (this is a W=1 build):
> (https://download.01.org/0day-ci/archive/20260917/202609172315.ZYoKvKBS-lkp@xxxxxxxxx/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Fixes: 721d90c8509a ("wifi: rtw89: add multicolor LED support for RTL8852CU valve board")
> | Reported-by: kernel test robot <lkp@xxxxxxxxx>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202609172315.ZYoKvKBS-lkp@xxxxxxxxx/
>
> All errors (new ones prefixed by >>):
>
> >> ld.lld: error: undefined symbol: led_classdev_multicolor_register_ext

Thanks for the report. This is because multicolor is kernel module

CONFIG_LEDS_CLASS_MULTICOLOR=m

but rtw89 is built-in

CONFIG_RTW89=y
CONFIG_RTW89_LEDS_MC=y

Correct the dependency in Kconfig to avoid this case. [1]

[1] https://lore.kernel.org/linux-wireless/20260918021113.25481-1-pkshih@xxxxxxxxxxx/T/#u