Public bug reported:

This issue has been reported several times before in various
forms. Typically about one national character missing. I try to
summarize all information I have collected in this new general report
and mark the earlier reports about special cases as duplicates.

 
Several non-ASCII characters get corrupted in the framebuffer
console. (see attached photos) This happens when returning from X back
to the console using Ctrl-Alt-F1 ...  Ctrl-Alt-F6.

The characters are are displayed correctly when booting into single
user mode and not starting X. (see attached
intrepid-single-user-OK.jpg) So the problem is not incomplete font
implementation or some locale issue. This is why I report the bug to
the kernel instead of to console-setup, if feels that console-setup
should not cause random pixel "characters" (But of course the bug could
really be somewhere else. I'm far from understanding completely how
this all works.) I also attach my /etc/defaults/console-setup

Actually the problem is described in /usr/share/doc/console-setup/FAQ.gz
However, it says that this happens only in text mode, not in framebuffer 
mode. So how can I find out in which mode my console is actually running?

I believe that my console should be in framebuffer mode, because:

$ lsmod | grep fb
fbcon                  47648  0 
tileblit               10880  1 fbcon
font                   16512  1 fbcon
bitblit                13824  1 fbcon

However there is a file /etc/modprobe.d/blacklist-framebuffer and it
says

# Framebuffer drivers are generally buggy and poorly-supported, and cause
# suspend failures, kernel panics and general mayhem.  For this reason we
# never load them automatically.

So do we use fbcon, but not the underlaying framebuffer???
Some documentation is here 
http://www.mjmwired.net/kernel/Documentation/fb/fbcon.txt, but I'm still 
confused.

The problem is not specifc to the reported kernel version. I see it
also with the current Hardy kernel and the Jaunty Beta LiveCD (see
jaunty-liveCD.jpg). The problem is not specific to the reported
grahics card. I see it also on Nvidia, on Radeon, and also on the
virtualized card created by VMware. The previously reported bugs (now
linked as duplicates) cover also various hardware and software
configurations.

I have tested the range Unicode U+00A0 ... U+00FF, my console coding
is UTF-8. http://www.utf8-chartable.de/ can be used for
referece. (From the previousily reported national character issues I
conclude that also characters outside this range are affected)
  
You can easily test yourself using the attached file

$ cat sampletable.txt
  
The character corruption comes in 2 different forms:

- Random pixel character range: All characters between and including
  U+00E9 and U+00FF are corrupted. Often the pixels are completely
  random (See attached intrepid-random-pixel-range.jpg) and they are
  different on each console tty1, tty2, ...  Sometimes they are just
  all white or black.

  The somehow weird thing is that the U+00E8 (e grave) is always the
  last character displayed correctly, whereas U+00E9 (e acute) is
  always the first corrupted character.

- missing accents. There is no random corruption in this case, but
  accents are missing from capital letters. It looks more like an
  intentional low-grade variant of the font. Accents are present on
  lowercase letters.  A couple of very rare characters (e.g. thorn)
  are displayed as white blocks.  (see attached
  intrepid-no-accents.jpg) I guess this variant of the problem may
  lead to the belief that a certain configuration is not affected, if
  you just test a couple of lowercase characters.

The same kernel on the same machine can sometimes show "random pixel
character range" and sometimes "missing accents". E.g. when boot first
into single user mode and start your X later in contrast of starting
everything the standard way. (intrepid-random-pixel-range.jpg and
intrepid-no-accents.jpg are from the same machine using the same kernel)


P.S. Not sure how important this problem really is. I started to dig
when investigating some serious display corruption (affecting also X
on framebuffer 7) So originally I thought if even the console gets
corrupted things are really bad. But in the meantime I have come to
the conclusion that this character corruption is most likely a
completely different issue from my original problem. For me personally
non-ASCII characters on the console are of minor importance. On the
other side according to Ubunutu philosophy software should be
available in the user's local language. This of course requires that
national characters work, if somebody works on the console.

ProblemType: Bug
Architecture: i386
DistroRelease: Ubuntu 8.10
Package: linux-image-2.6.27-14-generic 2.6.27-14.30
ProcCmdLine: root=UUID=f6bf9b65-0cad-45bd-b3a0-a7353a3900af ro quiet splash
ProcEnviron:
 PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
 LANG=fi_FI.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.27-14.30-generic
SourcePackage: linux

** Affects: linux (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: apport-bug

-- 
Non-ASCII characters get corrupted in framebuffer console
https://bugs.launchpad.net/bugs/355057
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