-vv does not give helpful new information in your case.
The SCSI command timeout for the write commands for
a DVD is 100 seconds. If sending a kill signal does not
show any result after 100 seconds, there must be a kernel bug.
Even though, your problem may be caused by a cable
problem (that caused a hung DMA), the kernel should be able
to abort things after the intended timeout.
You should contact the Linux kernel folks for help.
-vv does not give helpful new information in your case.
The SCSI command timeout for the write commands for
a DVD is 100 seconds. If sending a kill signal does not
show any result after 100 seconds, there must be a kernel bug.
Even though, your problem may be caused by a cable
problem (that caused a hung DMA), the kernel should be able
to abort things after the intended timeout.
You should contact the Linux kernel folks for help.