I don't see why there is a memory barrier in copy_from_read_buf() at all. Even if it was useful spin_unlock_irqrestore implies a barrier.
Signed-off-by: Ralf Baechle <[EMAIL PROTECTED]> diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c index 603b9ad..8df7ff3 100644 --- a/drivers/char/n_tty.c +++ b/drivers/char/n_tty.c @@ -1151,7 +1151,6 @@ static int copy_from_read_buf(struct tty n = min(*nr, n); spin_unlock_irqrestore(&tty->read_lock, flags); if (n) { - mb(); retval = copy_to_user(*b, &tty->read_buf[tty->read_tail], n); n -= retval; spin_lock_irqsave(&tty->read_lock, flags); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/