r almost all of it: # sort -nr /sys/kernel/slab/kmalloc-2048/alloc_calls 6402 .cfq_init_queue+0xec/0x460 age=43423/43564/43655 pid=1 cpus=4,11,13 In scsi_alloc_sdev we do scsi_alloc_queue but if slave_alloc fails we don't free it with scsi_free_queue. The patch below fixes the issue: OBJS ACTIVE USE OBJ SIZE SLABS OBJ/SLAB CACHE SIZE NAME 135 72 53% 2.30K 5 27 320K kmalloc-2048 # cat /sys/kernel/slab/kmalloc-2048/alloc_calls 3 .cfq_init_queue+0xec/0x460 age=3811/3876/3925 pid=1 cpus=4,11,13 Signed-off-by: Anton Blanchard Cc: #2.6.38+ Signed-off-by: James Bottomley  },’*x