Re: [PATCH 2/2] bus: mhi: ep: Add loopback driver for data path testing

[kernel test robot <lkp@intel.com>]

Hi Sumit,

kernel test robot noticed the following build errors:

[auto build test ERROR on e6b9dce0aeeb91dfc0974ab87f02454e24566182]

url:    https://github.com/intel-lab-lkp/linux/commits/Sumit-Kumar/bus-mhi-host-Add-loopback-driver-with-sysfs-interface/20250923-144109
base:   e6b9dce0aeeb91dfc0974ab87f02454e24566182
patch link:    https://lore.kernel.org/r/20250923-loopback_mhi-v1-2-8618f31f44aa%40oss.qualcomm.com
patch subject: [PATCH 2/2] bus: mhi: ep: Add loopback driver for data path testing
config: loongarch-randconfig-001-20250929 (https://download.01.org/0day-ci/archive/20250929/202509290238.4kkJL0x5-lkp@intel.com/config)
compiler: loongarch64-linux-gcc (GCC) 12.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250929/202509290238.4kkJL0x5-lkp@intel.com/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
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509290238.4kkJL0x5-lkp@intel.com/

All errors (new ones prefixed by >>):

   loongarch64-linux-ld: drivers/bus/mhi/ep/mhi_ep_loopback.o: in function `mhi_ep_loopback_dl_callback':
>> mhi_ep_loopback.c:(.text+0x20): undefined reference to `sk_skb_reason_drop'
   loongarch64-linux-ld: drivers/bus/mhi/ep/mhi_ep_loopback.o: in function `mhi_ep_loopback_work_handler':
   mhi_ep_loopback.c:(.text+0x74): undefined reference to `sk_skb_reason_drop'
   loongarch64-linux-ld: drivers/bus/mhi/ep/mhi_ep_loopback.o: in function `mhi_ep_loopback_ul_callback':
>> mhi_ep_loopback.c:(.text+0x19c): undefined reference to `__alloc_skb'
>> loongarch64-linux-ld: mhi_ep_loopback.c:(.text+0x1e4): undefined reference to `skb_put'
>> loongarch64-linux-ld: mhi_ep_loopback.c:(.text+0x2b8): undefined reference to `sk_skb_reason_drop'

-- 
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