Propagate cdrom_id errors caused by driver problems to the user

[paulmenzel]

Can udisks propagate driver errors to the user?

$ cdrom_id -d /dev/sr0
probing: '/dev/sr0'
INQUIRY failed
ID_CDROM=1

(This patch fixes this in Linux, but it took a while to figure the problem out.

[tbzatek]

cdrom_id is part of udev and we use udev database to gather common information from. In addition to that, udisks does further probing for certain type of devices.

So most driver errors will get handled by udev itself, for the rest we just print an error on stderr but there's no need to bother user with it unless error happens during handling of a method call.

Is that what you had on mind?

[paulmenzel]

Hmm, not sure. Here my use case:

Inserting a video DVD or audio CD into the external drive, nothing was automatically started and nothing was shown by a file manager like Nautilus. Even the CD program didn’t recognize a CD. Only VLC was able to play the DVD, but not the audio CD. It would have been nice, if the INQUIRY failed message would have been somehow visible in the logs (for the administrator) or the user have gotten some feedback like, that it’s probably a driver error.

[tbzatek]

I see. We've discussed similar matter some time ago, there's an idea for system-wide storage notification and alert framework but most likely this will be out of scope of udisks.

For the moment have a look at system logs, expect some messages from udev or kernel. DVD playback may work by direct access to the block device for de-CSS stuff to do the job, however playback of other type of media may not work due to lack of information from udev side.