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    SubjectRe: ethtool documentation
    > The EEPROM (SEEPROM) on these NICS is used to contain the startup
    > configuration bits and the IEEE Station Address. This must be a
    > unique number that is assigned so that there is no other such
    > number in (preferably) the world, and certainly in the LAN.
    > If you let a user write to this area, you will allow the user
    > to destroy the connectivity on a LAN.
    > If you provide an ioctl() to write new SEEPROM contents, it had
    > better be disabled in code that user's (any, including root)
    > can execute because, if caught, your company may lose it's IEEE
    > Station Addresses and never again be allowed to configure Ethernet
    > Controllers.

    I think you overstate the seriousness here - it's not unheard of for
    manufacturers to ship hardware with duplicate MAC addresses - a trivial
    search on Google turns up Cisco as one offender:

    > Because of this, there is no such thing as 'unused eeprom space' in
    > the Ethernet Controllers. Be careful about putting this weapon in
    > the hands of the 'public'. All you need is for one Linux Machine
    > on a LAN to end up with the same IEEE Station Address as another
    > on that LAN and connectivity to everything on that segment will
    > stop. You do this once at an important site and Linux will get a
    > very black eye.

    Worse than GE?

    Being able to permanently fix a screwed up card that duplicated another
    card on my LAN would be nice, imo.

    Of course, this assumes that IEEE Station Address == MAC address.

    Ryan Anderson
    sometimes Pug Majere
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