On Mon, 23 Mar 2015, Marc Joliet wrote: > Am Mon, 23 Mar 2015 11:34:59 +0100 > schrieb Marc Joliet <marcec@xxxxxx>: > > [...] > > > - Same as above, but this time I load the uas module before plugging in the > > > drive (I could have used usb-storage, but didn't out of mental habit). This > > > time the sector size is detected correctly. There are almost 16000 lines of > > > usbmon output from this, which is... a lot to look through for stuff to trim. > > > > > > So in summary, I'm confused. Why would the drive work correctly when I plug it > > > in after the fact, but not when it is plugged in before the system boots? > > OK, here's the first ~250 lines of usbmon output from this. The relevant bits > from the system log from when this file was generated: > > Mär 23 00:53:28 marcec kernel: usbcore: registered new interface driver usb-storage > Mär 23 00:53:28 marcec kernel: usbcore: registered new interface driver uas > Mär 23 00:53:59 marcec kernel: usb 4-2: new SuperSpeed USB device number 2 using xhci_hcd > Mär 23 00:53:59 marcec kernel: usb-storage 4-2:1.0: USB Mass Storage device detected > Mär 23 00:53:59 marcec kernel: scsi host8: usb-storage 4-2:1.0 > Mär 23 00:54:09 marcec kernel: scsi 8:0:0:0: Direct-Access Toshiba External USB 3.0 0201 PQ: 0 ANSI: 6 > Mär 23 00:54:09 marcec kernel: sd 8:0:0:0: Attached scsi generic sg6 type 0 > Mär 23 00:54:09 marcec kernel: sd 8:0:0:0: [sdf] Very big device. Trying to use READ CAPACITY(16). > Mär 23 00:54:09 marcec kernel: sd 8:0:0:0: [sdf] 732566645 4096-byte logical blocks: (3.00 TB/2.72 TiB) > Mär 23 00:54:09 marcec kernel: sd 8:0:0:0: [sdf] Write Protect is off > Mär 23 00:54:09 marcec kernel: sd 8:0:0:0: [sdf] Mode Sense: 2b 00 00 00 > Mär 23 00:54:09 marcec kernel: sd 8:0:0:0: [sdf] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA > Mär 23 00:54:09 marcec kernel: sd 8:0:0:0: [sdf] 732566645 4096-byte logical blocks: (3.00 TB/2.72 TiB) > Mär 23 00:54:09 marcec kernel: sdf: sdf1 sdf2 > Mär 23 00:54:09 marcec kernel: sd 8:0:0:0: [sdf] 732566645 4096-byte logical blocks: (3.00 TB/2.72 TiB) > Mär 23 00:54:09 marcec kernel: sd 8:0:0:0: [sdf] Attached SCSI disk > Mär 23 00:54:11 marcec kernel: BTRFS: device label MARCEC_BACKUP devid 1 transid 66044 /dev/sdf2 > Mär 23 00:54:12 marcec kernel: EXT4-fs (sdf1): mounted filesystem with ordered data mode. Opts: (null) > Mär 23 00:54:12 marcec udisksd[752]: Mounted /dev/sdf1 (system) at /media/TOSHIBA EXT on behalf of uid 1000 > Mär 23 00:54:12 marcec kernel: BTRFS info (device sdf2): disk space caching is enabled > Mär 23 00:54:12 marcec kernel: BTRFS: has skinny extents > Mär 23 00:54:18 marcec udisksd[752]: Mounted /dev/sdf2 (system) at /media/MARCEC_BACKUP on behalf of uid 1000 > > So, you know, everything behaving as expected, apparently. Yes, the usbmon trace confirms this. It's kind of odd, though. First the computer sends a READ CAPACITY(10), and the drive responds by saying that it has more than 4 billion 512-byte blocks. Then the computer sends READ CAPACITY(16), and the drive responds by saying that it has 732566645 (less than 4 billion!) 4096-byte blocks. There's no way to know why it changes its mind about the block size. When the computer sends another READ CAPACITY(10) command later on, the drive says the block size is 4096. It really does send different responses to the same command at different times. 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
