Bug#926717: linux-image-4.19.0-4-amd64: Size of DVD in external drive not recognised properly
Another update:
The also works with FreeBSD. I only checked in a VM but since the USB device is passed through that should not affect the result. FreeBSD provides the following information when connection the DVD drive
> ugen1.2: <Hitachi-LG Data Storage Inc Portable Super Multi Drive> at usbus1
> umass0 on uhub0
> umass0: <6238--Storage> on usbus1
> umass0: 8070i (ATAPI) over Bulk-Only; quirks = 0x0100
> umass0:2:0: Attached to scbus2
> cd0 at umass-sim0 bus 0 scbus2 target 0 lun 0
> cd0: <HL-DT-ST DVDRAM GP57EB40 PF01> Removable CD-ROM SCSI device
> cd0: 40.000MB/s transfers
> cd0: 3794MB (1942528 2048 byte sectors)
> cd0: quirks=0x10<10_BYTE_ONLY>
These test also lead to another interesting observation: Assigning the drive to a VirtualBox VM (FreeBSD in this case) and then giving it back it to the native Linux, will make it properly recognize the DVD currently in the drive. Unloading and reloading the 'usb-storage' kernel module has a similar effect. I tried the available quirks of the 'usb-storage' module (especially 'US_FL_INITIAL_READ10' looked promising), but to no avail.
Regards, Jan
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