On Thu, 18 Mar 2010, Jeff Garzik wrote: > Removing 61-option-modem-modeswitch.rules completely yields substantial > progress. A large number of SCSI commands are successfully processed, > eventually proceeding to a loop: > > [non-looping initial bit] > > hub 4-0:1.0: over-current change on port 7 > > usb 3-2: new full speed USB device using uhci_hcd and address 2 > > usb 3-2: New USB device found, idVendor=04e8, idProduct=6640 > > usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0 > > usb 3-2: Product: SAMSUNG CDMA Technologies > > usb 3-2: Manufacturer: SAMSUNG Electronics Bo.,Ltd. > > cdc_acm 3-2:1.0: ttyACM0: USB ACM device > > usbcore: registered new interface driver cdc_acm > > cdc_acm: v0.26:USB Abstract Control Model driver for USB modems and ISDN adapters > > usb 3-2: USB disconnect, address 2 > > usb 3-2: new full speed USB device using uhci_hcd and address 3 > > usb 3-2: New USB device found, idVendor=05c6, idProduct=1000 > > usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3 > > usb 3-2: Product: USB MMC Storage > > usb 3-2: Manufacturer: Qualcomm, Incorporated > > usb 3-2: SerialNumber: 000000000002 > > Initializing USB Mass Storage driver... > > scsi6 : usb-storage 3-2:1.0 > > usbcore: registered new interface driver usb-storage > > USB Mass Storage support registered. > > scsi 6:0:0:0: Direct-Access Qualcomm MMC Storrage 2.31 PQ: 0 ANSI: 2 > > sd 6:0:0:0: Attached scsi generic sg4 type 0 > > sd 6:0:0:0: [sdd] 3932161 512-byte logical blocks: (2.01 GB/1.87 GiB) > > sd 6:0:0:0: [sdd] Write Protect is off > > sd 6:0:0:0: [sdd] Assuming drive cache: write through > > sd 6:0:0:0: [sdd] Assuming drive cache: write through > > sdd: sdd1 > > sd 6:0:0:0: [sdd] Assuming drive cache: write through > > sd 6:0:0:0: [sdd] Attached SCSI removable disk > > [endless loop bit] > > sd 6:0:0:0: [sdd] Media Changed > > sd 6:0:0:0: [sdd] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE > > sd 6:0:0:0: [sdd] Sense Key : Unit Attention [current] > > sd 6:0:0:0: [sdd] Add. Sense: No additional sense information > > sd 6:0:0:0: [sdd] CDB: Read(10): 28 00 00 3c 00 00 00 00 01 00 > > end_request: I/O error, dev sdd, sector 3932160 > > Buffer I/O error on device sdd, logical block 3932160 > > sd 6:0:0:0: [sdd] Assuming drive cache: write through > > sd 6:0:0:0: [sdd] Assuming drive cache: write through > > sdd: sdd1 This looks like a familiar firmware bug. Notice the sector number; it's the very last one. Most likely this device reports that the medium has one more sector than it really does have. You didn't say which kernel produced this output; I kind of hope the most recent 2.6.34 version would do a better job of error recovery. Regardless, you can work around the last-sector problem by loading usb-storage with the module parameter "quirks=5c6:1000:f". A more permanent solution would involve adding an entry to the unusual_devs.h file in drivers/usb/storage/. 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
