Okay everyone, it goes deeper! I tried recompiling the Linux kernel to incorporate a few changes and to see if I could get dmraid to work correctly. The following is my result: ubuntu/built-in.o: In function `dm_rh_dec': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:527: multiple definition of `dm_rh_dec' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:535: first defined here ubuntu/built-in.o: In function `dm_rh_delay': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:673: multiple definition of `dm_rh_delay' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:687: first defined here ubuntu/built-in.o: In function `dm_rh_recovery_in_flight': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:661: multiple definition of `dm_rh_recovery_in_flight' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:675: first defined here ubuntu/built-in.o: In function `dm_rh_update_states': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:431: multiple definition of `dm_rh_update_states' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:437: first defined here ubuntu/built-in.o: In function `dm_rh_start_recovery': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:707: multiple definition of `dm_rh_start_recovery' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:708: first defined here ubuntu/built-in.o: In function `dm_rh_mark_nosync': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:393: multiple definition of `dm_rh_mark_nosync' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:395: first defined here ubuntu/built-in.o: In function `dm_region_hash_destroy': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:230: multiple definition of `dm_region_hash_destroy' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:235: first defined here ubuntu/built-in.o: In function `dm_rh_region_to_sector': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:118: multiple definition of `dm_rh_region_to_sector' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:122: first defined here ubuntu/built-in.o: In function `dm_rh_dirty_log': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:255: multiple definition of `dm_rh_dirty_log' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:260: first defined here ubuntu/built-in.o: In function `dm_rh_stop_recovery': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:697: multiple definition of `dm_rh_stop_recovery' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:698: first defined here ubuntu/built-in.o: In function `dm_rh_bio_to_region': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:124: multiple definition of `dm_rh_bio_to_region' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:128: first defined here ubuntu/built-in.o: In function `dm_rh_recovery_prepare': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:604: multiple definition of `dm_rh_recovery_prepare' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:619: first defined here ubuntu/built-in.o: In function `dm_rh_recovery_start': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:627: multiple definition of `dm_rh_recovery_start' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:642: first defined here ubuntu/built-in.o: In function `dm_rh_flush': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:667: multiple definition of `dm_rh_flush' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:681: first defined here ubuntu/built-in.o: In function `dm_rh_region_context': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:130: multiple definition of `dm_rh_region_context' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:134: first defined here ubuntu/built-in.o: In function `dm_region_hash_create': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:163: multiple definition of `dm_region_hash_create' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:167: first defined here ubuntu/built-in.o: In function `dm_rh_get_region_key': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:136: multiple definition of `dm_rh_get_region_key' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:140: first defined here ubuntu/built-in.o: In function `dm_rh_inc_pending': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:518: multiple definition of `dm_rh_inc_pending' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:523: first defined here ubuntu/built-in.o: In function `dm_rh_get_state': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:333: multiple definition of `dm_rh_get_state' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:338: first defined here ubuntu/built-in.o: In function `dm_rh_get_region_size': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:142: multiple definition of `dm_rh_get_region_size' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:146: first defined here ubuntu/built-in.o: In function `dm_rh_recovery_end': /home/erick/Desktop/linux-source-2.6.35/ubuntu/dm-raid4-5/dm-region-hash.c:643: multiple definition of `dm_rh_recovery_end' drivers/built-in.o:/home/erick/Desktop/linux-source-2.6.35/drivers/md/dm-region-hash.c:658: first defined here make: *** [vmlinux.o] Error 1 There is officially a problem with the dm-raid4-5 module in the Linux kernel.