Alan / Simon -- If you look at the device descriptors, it reports itself as an SFF-8020i device. This kicks-in code to force all commands to 12-byte, as (I think) required by 8020i. Of course, for a large device like this, you might need 16-byte commands. This probably needs a protocol override to force it back to transparent SCSI mode. Either that, or someone needs to take a longer look at the 8020 spec, 8020 devices, and see if there is a way to make it work without an override... Matt On Mon, Oct 24, 2011 at 8:54 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Mon, 24 Oct 2011, Simon Detheridge wrote: > >> > > Any ideas as to what I can do to make this work? >> > >> > The best way to start is to get a usbmon trace. There are instructions >> > in the kernel source file Documentation/usb/usbmon.txt. >> >> Thanks for your reply. >> >> I ran usbmon, and inserted the drive. I didn't run any further commands after insertion, just watched to see what happened. >> >> Dmesg said this: >> http://pastebin.com/3v2ihQic >> >> Meanwile, usbmon said: >> http://pastebin.com/38ZxSg6d >> (I have no idea what any of that means!) > > Fortunately, I do! :-) > > The trace shows that an invalid READ(16) command was sent to the drive. > In fact, you can see it in the dmesg log: > > [ 2603.289546] sd 9:0:0:0: [sde] CDB: Read(16): 88 00 00 00 00 01 5d 50 a3 00 00 00 > > 88 is indeed READ(16), but the command is supposed to be 16 bytes long, > not 12 -- that's what the "(16)" in the name means. The drive should > have refused to carry out the command and returned an error code, but > instead it tried to do the command and then hung. > > It's hard to tell where that command came from, but since it was one of > the first commands sent, it was probably some program associated with > udev or ConsoleKit or something like that. You may be able to find out > which program it was by running ps or lsof during the delays while the > system is trying to read the drive. > > Alan Stern > > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Matthew Dharm Maintainer, USB Mass Storage driver for Linux -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
