(Emacs: -*- indented-text -*-)

			 A list of known bugs
		Copyright (c) 1996 - 1999 Ulrich Windl
		 <Ulrich.Windl@rz.uni-regensburg.de>
		     $Date: 1999/10/28 17:52:37 $

- A long-lasting bug in the Linux kernel is the incorrect updates to
  the CMOS clock, especially during daylight saving time.  Since
  kernel 2.0.32/2.2.0 a kernel warning is printed at least. It's not
  quite obvious how to fix it without knowing the hardware very well
  (it seems).

- Architectures other than i386 are possibly still incomplete, but
  should be rather straight forward (files <arch>/kernel/time.c,
  include/asm-<arch>/{ioctls.h,termios.h}).  See the changes made to
  the common files and for i386 architecture.

- The line discipline code should be revised.

- For multiple CPUs the cycle counters may vary significantly.  When
  changing CPUs from interrupt to interrupt, the time offset may jump
  within one tick, probably even backwards (but that's filtered away)!

- Some Linux extensions within ``adjtimex()'' (which happens to be
  used as ``ntp_adjtime()'') collided with bits newly introduced by
  the nanokernel.  Therefore the bits had to be moved, breaking binary
  compatibility for the following flags and routines:
  ``ADJ_OFFSET_SINGLESHOT'' (``ADJ_ADJTIME'' now), ``ADJ_TICK'',
  ``ADJ_TICKADJ'', adjtime().  The latter two collide with
  ``STA_NANO'' and ``STA_CLK''.  Fortunately the first one can be
  mapped to the correct function while the last two are quite rarely
  used.

- If compilation fails, please check if ``<sys/timex.h>'' really is
  ``/usr/src/linux/include/timex.h''.  Some glibc-2.1 systems ship
  their own version of ``<sys/timex.h>''.  Reg Clemens <reg@dwf.com>
  confirmed that RedHat 6.0 (and 5.x, too) systems show this bug.

- If the serial port is closed, all special flags are reset; it the
  port is opened again, the interrupt enable register may loose the
  bit for modem status changes, causing high jitter.
