Bug#998718: Brasero fails (on Testing) burning an ISO image on a CD-RW

[Thomas Schmitt]

Hi,

what i believe to have learned so far:

- The problem is a co-operation of ASUS DRW-24D5MT and Brasero or
  some software which Brasero employs. This other software (if involved
  at all) does not strike with K3B (tested by Mauro Sacchetto) or
  non-GUI burn programs like wodim or xorriso.

- The problem happens only with CD media. This media family is the most
  complicated among the optical media, because it not only can record
  data blocks of 2048 bytes per sector but also other sector types
  like CD-DA with 2352 bytes.

- Reading data CD by audio CD commands is supposed to fail on the first
  read attempt, but the ASUS DRW-24D5MT tolerates this against the SCSI
  specs. The drive announces the obsolete feature 103h "CD Audio External
  Play Feature". (PIONEER BDR-S09 does not. TSSTcorp SH-S223B does, but
  throws the specified error when reading data CD as audio CD.)
  Weak theory:
  This tolerance might lure Brasero or other software into sending SCSI
  commands which are inappropriate with data CD, like the obsolete SCAN
  command or the obsolete STOP PLAY/SCAN command. These commands were
  obsoleted in 2006 by MMC-5 together with the PLAY AUDIO and other
  commands which were specific to standalone playing of audio CD.
  (All drives still support READ CD which can be used to read audio
   CD into the computer and let its media players create sound.)

- There seems to be involved a difference between Cinnamon of Debian
  Testing and XFCE of Debian 10. While Mauro Sacchetto does not get an
  unusable drive with Brasero and a blank CD-RW on Cinnamon, i get to
  that problem after writing succeeded but before the checksum gets
  verified by Brasero. (The CD verifies good in another drive by
  comparing the MD5s of ISO image and CD.)
  With non-blank CD-RW i experienced sometimes the problem already
  after inserting it into the ASUS drive while Brasero is running.
  Mauro Sacchetto did not report such an early problem.

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Open questions:

- Would it happen without desktop ?
  E.g. with fvwm2 as window manager.

- Is udisks involved ?
  It seems to be very eager to automount as soon as the CD contains
  data. When i kill its process, they come back quickly.

- Is the XFCE (?) window involved which offers a file manger even for
  blank CDs when they get inserted ?

- Is the way of attachment of the drive to the computer involved ?
  My TSSTcorp drive offers obsolete CD audio commands but is in a
  USB box, whereas the ASUS is directly at SATA.

- Why does only Brasero invite the problem ?

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Have a nice day :)

Thomas