On 2/10/2014 5:11 AM, Hannes Reinecke wrote: > EVPD page 0x83 is used to uniquely identify the device. So instead of > having each and every program issue a separate SG_IO call to retrieve this > information it does make far more sense to display it in sysfs. Tested-by: Jeremy Linton <jlinton@xxxxxxxxxxxxx> So, I just ran it in 3.14-rc2. No OOPS, that is good. It even survived probing a SPC-2 device without a page 0x83. I tested it with a fairly narrow set of devices, a couple IBM libraries with LTO/359x and a VTL. I did notice this on an old IBM raid adapter running in the machine cat: ident_lun_scsi_name: Invalid argument (that came from this device) sg_inq --page=0x83 --hex /dev/sg2 VPD INQUIRY, page code=0x83: 00 00 83 00 48 01 03 00 08 50 01 0b 90 00 12 1d 90 ...H....P....... 10 61 93 00 08 50 01 0b 90 00 12 1d 8e 61 94 00 04 a...P.......a... 20 00 00 00 01 61 a3 00 08 50 01 0b 90 00 12 1d 8d ....a...P....... 30 63 a8 00 18 6e 61 61 2e 35 30 30 31 30 42 39 30 c...naa.50010B90 40 30 30 31 32 31 44 38 44 00 00 00 00 00121D8D.... And there may be a couple descriptors missing here and there. For example 3592E05 is missing the total port count (I think). VPD INQUIRY, page code=0x83: 00 01 83 00 5c 02 01 00 24 49 42 4d 20 20 20 20 20 ...\...$IBM 10 30 33 35 39 32 45 30 35 20 20 20 20 20 20 20 20 03592E05 20 30 30 30 30 30 37 38 33 36 33 32 33 01 03 00 08 000007836323.... 30 50 05 07 63 02 41 0c 2c 01 13 00 08 50 05 07 63 P..c.A.,....P..c 40 02 81 0c 2c 01 14 00 04 00 00 00 02 01 23 00 08 ...,.........#.. 50 50 05 07 63 02 41 0c 2c 01 24 00 04 00 00 00 01 P..c.A.,.$...... /sys/class/scsi_tape/nst14/device # ls ident_* ident_lun_naa ident_lun_t10 ident_port_naa ident_port_relport ident_target_naa This almost seems like a case where exporting the raw 0x83 data may be better... Also, as I stated previously, my personal bias is to include the page 0x80 serial number data for tape devices as well. That seems to be the most reliable. Mostly because a lot of the VTLs now just give you the same wwnn/wwpn in 0x83 for multiple LUNs. Meaning you can't uniquely identify the device over different physical ports. The IBM devices are nice in that they export a T10 Vendor ID with the man/model/serial in 0x83, but that is not common in my experience. For example (old T10k) VPD INQUIRY, page code=0x83: 00 01 83 00 20 01 03 00 08 50 01 04 f0 00 93 ac f6 ... ....P....... 10 01 13 00 08 50 01 04 f0 00 93 ac f7 01 14 00 04 ....P........... 20 00 00 00 01 .... -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html