Re: [PATCH iwl-net] idpf: select AUXILIARY_BUS to fix link failure

[Przemek Kitszel <przemyslaw.kitszel@intel.com>]

On 11/11/26 8:31 PM, Darren Worrall via B4 Relay wrote:
> From: Darren Worrall <darren.worrall@shopify.com>
> 
> The build can currently fail with
> 
>      ld: vmlinux.o: in function `idpf_plug_vport_aux_dev':
>      drivers/net/ethernet/intel/idpf/idpf_idc.c:82: undefined reference to `auxiliary_device_init'
>      ld: drivers/net/ethernet/intel/idpf/idpf_idc.c:86: undefined reference to `__auxiliary_device_add'
>      ld: vmlinux.o: in function `idpf_plug_core_aux_dev':
>      drivers/net/ethernet/intel/idpf/idpf_idc.c:223: undefined reference to `auxiliary_device_init'
>      ld: drivers/net/ethernet/intel/idpf/idpf_idc.c:227: undefined reference to `__auxiliary_device_add'
> 
> if IDPF is enabled but no other driver pulls in AUXILIARY_BUS. We hit
> this building a minimal kernel for hosts with IDPF NICs. It can be
> reproduced on x86_64 from allnoconfig by enabling PCI, PCI_MSI, NET,
> NETDEVICES, ETHERNET, NET_VENDOR_INTEL and IDPF.
> 
> Select AUXILIARY_BUS in IDPF, as ICE and I40E already do. The same
> link failure was fixed for BNGE in commit d7065436e8a0 ("net: bnge: add
> AUXILIARY_BUS to Kconfig dependencies").
> 
> Build-tested with that configuration on net-queue (dev-queue,
> 34a70a40c954) and on mainline (067c5c24cef2): vmlinux fails to link
> without this patch and links with it. Boot-tested on bare metal (AMD
> EPYC) with a Google Cloud IDPF NIC, using a 6.18.60 kernel carrying the
> same change and IDPF built in: idpf probes the NIC and its link comes
> up.
> 
> Fixes: f4312e6bfa2a ("idpf: implement core RDMA auxiliary dev create, init, and destroy")
> Cc: stable@vger.kernel.org # 6.17+
> Signed-off-by: Darren Worrall <darren.worrall@shopify.com>

Thank you!
Acked-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>


> ---
> The link failure was diagnosed, this patch drafted and the tests above
> run with the help of an AI coding assistant. I reviewed the patch and
> the test results.
> ---
>   drivers/net/ethernet/intel/idpf/Kconfig | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/ethernet/intel/idpf/Kconfig b/drivers/net/ethernet/intel/idpf/Kconfig
> index 586df3a4af..6b59173e0d 100644
> --- a/drivers/net/ethernet/intel/idpf/Kconfig
> +++ b/drivers/net/ethernet/intel/idpf/Kconfig
> @@ -5,6 +5,7 @@ config IDPF
>   	tristate "Intel(R) Infrastructure Data Path Function Support"
>   	depends on PCI_MSI
>   	depends on PTP_1588_CLOCK_OPTIONAL
> +	select AUXILIARY_BUS
>   	select DIMLIB
>   	select LIBIE_CP
>   	select LIBETH_XDP
> 
> ---
> base-commit: 34a70a40c954fb8044ecd124840a2c38cd3aa4cc
> change-id: 20261111-idpf-auxiliary-bus-c0058e27cd9d
> 
> Best regards,
> --
> Darren Worrall <darren.worrall@shopify.com>
> 
>