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    SubjectRe: [PATCH] root-hopping for pre-2.3.41-3
    Followup to:  <>
    By author: Guest section DW <>
    In newsgroup:
    > and Peter answered
    > > > Right... everyone on the old / move to the new /, although I guess
    > > > that's technically not 100% necessary.
    > but I wonder.
    > Usually in such a situation not many processes will be around, but still..
    > It would be strange if the interpretation of paths suddenly changed for
    > processes other than the one doing this pivot_root.
    > So, I would prefer these old processes all to remain where they are,
    > with the same root inode (that just got a new name, namely /old_root).
    > Thus, the only process that would get the new / as root would be the
    > process doing this pivot_root() (and perhaps init?).

    I think this really is the right solution... usually the process doing
    this will *be* init. There are other things that need to be done,
    too, like replacing the console fd's after the remount (otherwise you
    will hold initrd busy by virtue of having /dev/console open.)

    I therefore conclude that doing automatic stuff is pointless and
    probably harmful. The recommended sequence for root-switching will
    then look something like (error checking omitted):

    pivot_root("/newroot", "/oldroot");
    new_console = open("/dev/console", O_RDWR);
    dup2(new_console, 0);
    dup2(new_console, 1);
    dup2(new_console, 2);

    execl("/sbin/init", "init", 0);
    <> at work, <> in private!
    "Unix gives you enough rope to shoot yourself in the foot."

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