Hitting eject on DVD drive does not result in media being unmounted. Putting in new DVD results in DVD read errors.
Steps to reproduce:
- enter DVD
- eject DVD using drive eject button
- put in different DVD
- $mount |grep sr0
DVD playback of new disk will not work and errors issue in dmesg such as:
[ 2348.391264] end_request: I/O error, dev sr0, sector 12134268
[ 2348.391267] Buffer I/O error on device sr0, logical block 3033567
Whilst I have seen it argued that a user should always unmount and eject using software and not via DVD drive optical button, to me it seems like a perfectly ordinary usage scenario to want to eject using the drive button, particularly in the case of ROM media.
Potentially of relevance:
Comment by Jan de Groot (JGC) on Archlinux bug report - Thursday, 25 September 2014, 14:54 GMT: I checked the /lib/udev/rules.d directory for rules concerning cdrom devices. When you insert media in /dev/sr* devices, udev locks the drive using the cdrom_id tool, mounted or not, it's locked. When you press the button, udev generates an eject event, which is passed to the cdrom_id tool with --eject. This tool doesn't check for any mounts, it just throws out the disk. You can reproduce this by running /usr/lib/udev/cdrom_id --eject /dev/sr0 as root, the drive will open and media is still mounted.
*** This bug has been marked as a duplicate of bug 72206 ***