make[3]: Entering directory '/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/linux-5.4.255'
  CC [M]  /mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.o
/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.c: In function 'fast_classifier_init':
/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.c:1888:1: warning: label 'exit4' defined but not used [-Wunused-label]
 exit4:
 ^~~~~
  Building modules, stage 2.
  MODPOST 1 modules
ERROR: "sfe_ipv6_register_sync_rule_callback" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv4_register_sync_rule_callback" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv6_update_rule" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv6_create_rule" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv4_update_rule" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv4_create_rule" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv6_recv" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv4_recv" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv6_mark_rule" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv6_destroy_rule" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv4_mark_rule" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv4_destroy_rule" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv4_destroy_all_rules_for_dev" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
ERROR: "sfe_ipv6_destroy_all_rules_for_dev" [/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/fast-classifier.ko] undefined!
make[4]: *** [scripts/Makefile.modpost:93: __modpost] Error 1
make[3]: *** [Makefile:1663: modules] Error 2
make[3]: Leaving directory '/mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/linux-5.4.255'
make[2]: *** [Makefile:70: /mnt/disk/openwrt-21.02/build_dir/target-aarch64_generic_musl/linux-layerscape_armv8_64b/fast-classifier/.built] Error 2
time: package/network/utils/fast-classifier/compile#2.08#0.44#3.67