I am recompiling 3.18.27 on a platform derived from el6. FIPS mode is enabled by checking the following configs: CONFIG_CRYPTO_FIPS=y CONFIG_CRYPTO_TEST=y Following RH docs, initramfs was regenerated using dracut-fips (el6). I also generated hmac signed vmlinuz during the compilation. During boot, kernel panics with the following trace: kernel line has the arguments, 'fips=1 boot=/dev/sda1'. "end Kernel Panic - not syncing: Module crc32c_intel signature verification failed in FIPS mode" Some additional info: It seems under fips mode, initrd runs, './sbin/fips.sh' which then runs 'modprobe tcrypt'. I tried running modprobe tcrypt without the fips mode on the same kernel, but it fails with this message. FATAL: Error inserting tcrypt (/lib/modules/3.18.27-1.timbuktu/kernel/crypto/tcrypt.ko.gz): Unknown symbol in module, or unknown parameter (see dmesg) Looking at dmesg: [ 31.248054] sha256_ssse3: Using AVX optimized SHA-256 implementation [ 31.308174] sha512_ssse3: Using AVX optimized SHA-512 implementation [ 31.407674] alg: No test for crc32 (crc32-pclmul) [ 31.408410] alg: No test for crc32 (crc32-table) [ 31.409086] alg: hash: Failed to load transform for hmac(crc32): -2 [ 31.413155] alg: No test for fips(ansi_cprng) (fips_ansi_cprng) [ 31.440281] tcrypt: one or more tests failed! Now, one of these messages, [ 31.409086] alg: hash: Failed to load transform for hmac(crc32): -2 comes, most likely from : linux-3.18.27/crypto/tcrypt.c (L1498) case 110: ret += tcrypt_test("hmac(crc32)"); break; and also from linux-3.18.27/crypto/testmgr.c .alg = "hmac(crc32)", .test = alg_test_hash, .suite = { .hash = { .vecs = bfin_crc_tv_template, .count = BFIN_CRC_TEST_VECTORS } } Any suggestion on how to solve this problem would be appreciated. Please let me know if I can provide more info. I am ready to help on that.