Re: [PLUG] USB memory stick

Greg Lopp <lopp@pobox.com> · 2005年11月09日 12:31:47 -0600

Jeff Abrahamson wrote:
I tried to use a USB memory stick yesterday. It looks like my kernel
(2.6.12) was fine with it, but then things didn't work out. Yet the
memory stick's owner said it worked fine on Windows and Mac boxes.
Any thoughts what I might have missed? The log entries follow:

 Nov 8 10:34:07 astra kernel: usb 1-2: new full speed USB device using uhci_hcd and address 3

 Nov 8 10:34:08 astra kernel: scsi1 : SCSI emulation for USB Mass Storage devices

 Nov 8 10:34:08 astra kernel: usb-storage: device found at 3

 Nov 8 10:34:08 astra kernel: usb-storage: waiting for device to settle before scanning

 Nov 8 10:34:09 astra usb.agent[24696]: usb-storage: already loaded

 Nov 8 10:34:13 astra kernel: Vendor: Kingston Model: DataTraveler 2.0 Rev: 4.10

 Nov 8 10:34:13 astra kernel: Type: Direct-Access ANSI SCSI revision: 02

Looking good. Not sure if this is the device-level enumeration or the 
mass-storage yet.
 Nov 8 10:34:13 astra kernel: SCSI device sdc: 503808 512-byte hdwr sectors (258 MB)

Definitely mass-storage here. Your kernel said READ_CAPACITY and the 
device replied that it has sectors of 512 bytes and 503808 of them.
 Nov 8 10:34:13 astra kernel: sdc: Write Protect is off

 Nov 8 10:34:13 astra kernel: sdc: Mode Sense: 0b 00 00 08

 Nov 8 10:34:13 astra kernel: sdc: assuming drive cache: write through

 Nov 8 10:34:13 astra kernel: SCSI device sdc: 503808 512-byte hdwr sectors (258 MB)

 Nov 8 10:34:13 astra kernel: sdc: Write Protect is off

 Nov 8 10:34:13 astra kernel: sdc: Mode Sense: 0b 00 00 08

 Nov 8 10:34:13 astra kernel: sdc: assuming drive cache: write through

Hmmm. A little odd to be repeating that.......
 Nov 8 10:34:13 astra kernel: /dev/scsi/host1/bus0/target0/lun0: [CUMANA/ADFS] p1<5>Attached scsi removable disk sdc at scsi1, channel 0, id 0, lun 0

Lun 0. OK. Only one logical storage medium/disk.
 Nov 8 10:34:13 astra kernel: usb-storage: device scan complete

 Nov 8 10:34:13 astra scsi.agent[25369]: sd_mod: loaded successfully (for disk)

???
 Nov 8 10:34:14 astra kernel: Buffer I/O error on device sdc1, logical block 508378384

 Nov 8 10:34:14 astra kernel: Buffer I/O error on device sdc1, logical block 508378384

 Nov 8 10:34:14 astra kernel: Buffer I/O error on device sdc1, logical block 508378412

 Nov 8 10:34:14 astra last message repeated 5 times

 Nov 8 10:34:14 astra kernel: Buffer I/O error on device sdc1, logical block 508378405

 Nov 8 10:34:14 astra kernel: Buffer I/O error on device sdc1, logical block 508378405

50,837,884 > 503,808

A mass storage device appears as a linear array of sectors to the 
kernel...er fs, whichever. The deviec informed us earlier that it has 
only 503808 of these sectors. Why on earth would the kernel be trying 
to look at logical sector 50,837,884? Could there be a funky partition 
table on the device? Can you read the partition table using "fdisk 
/dev/sdc" ? 
I have some mods I've made to a 2.6.10 kernel for looking a little 
deeper into the mass-storage communication. It is just some more 
verbose debugging. Let me know if you'd like them.

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