Hi, (I am currently not subscribed to linux-scsi but will do if a discussion arises. Just give me a note by direct mail.) Alba Pompeo wrote: > [ 9.698784] sr 1:0:0:0: [sr0] tag#12 Sense Key : 0x4 [current] > [ 9.698788] sr 1:0:0:0: [sr0] tag#12 ASC=0x3e ASCQ=0x2 > [ 9.698795] sr 1:0:0:0: [sr0] tag#12 CDB: opcode=0x28 28 00 00 00 ae 96 00 00 02 00 4 3E 02 TIMEOUT ON LOGICAL UNIT Quite a harsh reaction for an attempt to read the TAO roun-out blocks. Normal would be rather something like 5 30 02 CANNOT READ MEDIUM INCOMPATIBLE FORMAT 5 64 00 ILLEGAL MODE FOR THIS TRACK > My best guess would be that this confuses the entity among the ISO > payload, which is in charge for creating /dev/disk/by-label/ links > while the system boots up. At least with Archlinux it is/was the program blkid. A few weeks ago i posted to linux-scsi Date: Sun, 28 Feb 2016 14:41:59 +0100 Subject: sr: Failures to read TAO CD track ends Message-Id: <6531578277915568387@xxxxxxxxxxxxxxxxxxxxxx> http://marc.info/?l=linux-scsi&m=145666692729714&w=2 with CD drive observations and remarks about drivers/scsi/sr.c and its strange theory of 75 block fuzziness of READ CAPACITY. The problem is rather about the last two blocks which are reported to be part of a TAO track. They need to be handled mistrustingly, because the CD drives show no uniform behavior with counting the unreadable run-out blocks as part of readable payload or not. As of april 19 2016 the problem gets circumvented in upstream libblkid: https://github.com/karelzak/util-linux/commit/bfebe74e3babe8c188a51269acc2673f1aea283f At least for me it solved the failure of blkid on a TAO CD. So it might be worth to inform the publishers of CD-sized ISOs that they can close the pitfall by updating the blkid program which they put into their ISOs. Have a nice day :) Thomas -- 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
