Building backports-4.4.2-1 (defconfig-rtlwifi) results with errors: backports-4.4.2-1/compat/crypto-ccm.c: In function ‘crypto_ccm_init_crypt’: backports-4.4.2-1/compat/crypto-ccm.c:361:2: error: implicit declaration of function ‘scatterwalk_ffwd’ [-Werror=implicit-function-declaration] backports-4.4.2-1/compat/crypto-ccm.c:361:5: warning: assignment makes pointer from integer without a cast [enabled by default] backports-4.4.2-1/compat/crypto-ccm.c:622:2: error: implicit declaration of function ‘aead_register_instance’ backports-4.4.2-1/compat/crypto-ccm.c:506:2: error: implicit declaration of function ‘crypto_aead_set_reqsize’ backports-4.4.2-1/compat/crypto-ccm.c:572:5: error: implicit declaration of function ‘aead_crypto_instance’ ... Kernel version: 3.10.10. CROSS_COMPILE=arm-buildroot-linux-uclibcgnueabi- ARCH=arm
We actually removed the ccm backport, it never functioned well, if at all, and is a pain to backport. Just put ccm into your base kernel instead, it's always been available.