Hi Ard, >> However, since the dependency for "crc10dif" is already satisfied, >> nothing is going to cause the hardware-accelerated kernel modules to >> get loaded. > > This is not true. All accelerated implementations based on SIMD > polynomial multiplication are tried to the respective CPU features > bits. This applies to x86, power, ARM and arm64. > > E.g., for x86 you have > > alias: cpu:type:x86,ven*fam*mod*:feature:*0081* > > which will be matched by udev if /sys/devices/system/cpu/modalias > contains feature 0081, and so the modules will be loaded automatically > at boot. If I can avoid carrying that init callback in the block integrity code that will definitely make me happy. However, loading crct10dif-pclmul does not happen automatically for me. crc-t10dif is linked statically and every user of the CRC goes through that library. So nothing ever requests the "crct10dif" modalias and no accelerator modules are loaded. <fresh boot> # lsmod | grep crc crc32c_intel 24576 0 crc_ccitt 16384 1 ipv6 # modinfo crc32c_intel | grep cpu:type alias: cpu:type:x86,ven*fam*mod*:feature:*0094* # modinfo crct10dif-pclmul | grep cpu:type alias: cpu:type:x86,ven*fam*mod*:feature:*0081* # egrep -o "0081|0094" /sys/devices/system/cpu/modalias 0081 0094 # modprobe crct10dif # lsmod | grep crc crct10dif_pclmul 16384 1 crc32c_intel 24576 0 crc_ccitt 16384 1 ipv6 It's interesting that crc32c_intel is loaded but libcrc32c is not. That matches your description of how things should work. But crct10dif-pclmul isn't loaded and neither is crc32_pclmul: # modprobe crc32 # lsmod | grep crc crc32_generic 16384 0 crc32_pclmul 16384 0 crc32c_intel 24576 0 crc_ccitt 16384 1 ipv6 -- Martin K. Petersen Oracle Linux Engineering
