----- "Bob Montgomery" <bob.montgomery(a)hp.com&gt; wrote: It means that a pointer to a file_operations either doesn't exist (or that I have no clue how to find it...) For the hell of it I added that -f flag to show those devices in case somebody's interested. I did see that, and I forget now how the old code found it (although the function still exists), but the structures being used now are bdev_map.probes[] and major_names[]: crash> whatis struct kobj_map struct kobj_map { struct probe *probes[255]; struct mutex *lock; } SIZE: 2048 crash> whatis major_names struct blk_major_name *major_names[255]; crash> where the kernel's kobj_map.probes[] array size is just hardwired to 255, and the major_names[] array size is BLKDEV_MAJOR_HASH_SIZE which is 255. So obviously 259 won't be found. If you want to figure out how to show it, send me a patch. At this point I'm about ready to deprecate the whole command... ;-) Dave