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    SubjectRe: /proc/scsi/map

    >
    > Both usb-storage and iee1394-sbp2 know the GUID. It only needs to be
    > communicated..
    >
    >The usb-storage GUID is just one random item of information.

    Why is this 'one random item' ??
    For usb-storage devices the GUID is built using Vendor ID & Device ID and
    the device's Serial Nr.

    For identification purposes, the serial number is useless without Vendor ID
    & Device ID.
    Ofcourse we'll never have a change of creating stable name for devices that
    don't have a serialnr.


    >One might wish for much more.
    >
    >And: this information is already somewhere:
    Sure. But
    a) not easily readable
    b) totall different for FireWire devices
    c) race-conditions (reading multiple files).



    >% cat /proc/scsi/usb-storage-0/2
    > Host scsi2: usb-storage
    > Vendor: DataFab Systems Inc.
    > Product: USB CF+SM
    >Serial Number: 5DC69477C6
    > Protocol: Transparent SCSI
    > Transport: Datafab Bulk-Only
    > GUID: 07c4a1090000005dc69477c6
    > Attached: Yes
    Exactly, but finding this out at the moment involves reading:
    /proc/scsi/scsi, scanning /proc/scsi/usb-storage-*, scanning
    /proc/scsi/usb-storage-X/*, reading /proc/scsi/usb-storage-X/Y.


    >% cat /proc/scsi/usb-storage-1/3
    > Host scsi3: usb-storage
    > Vendor: SCM Microsystems Inc.
    > Product: eUSB SmartMedia / CompactFlash
    >Serial Number: None
    > Protocol: Transparent SCSI
    > Transport: Control/Bulk-EUSB/SDDR09
    > GUID: 04e600050000000000000000
    > Attached: Yes

    Well that's just SCM, huh ? The newer SCM-Orca chipset has a S/N.



    >Finally, the GUIDs you see here do not determine the LUN.
    >So, there is no well-defined line in /proc/scsi/map
    >where they would belong.

    But the LUN-map for such a device will never change ?
    Incase a device has 4 LUN's, well have 4 /proc/scsi/map entries with the
    same GUID.

    The hotplug agent will indeed be watching GUID+Lun.

    - sda

    -
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