linux-stable.git/drivers/tty/vt, branch v3.2.41

fb: Yet another band-aid for fixing lockdep mess

2013-03-06T03:23:52+00:00

commit e93a9a868792ad71cdd09d75e5a02d8067473c4e upstream.

I've still got lockdep warnings even after Alan's patch, and it seems that
yet more band aids are required to paper over similar paths for
unbind_con_driver() and unregister_con_driver().  After this hack, lockdep
warnings are finally gone.

Signed-off-by: Takashi Iwai 
Cc: Alan Cox 
Cc: Florian Tobias Schandinat 
Cc: Jiri Kosina 
Tested-by: Sedat Dilek 
Signed-off-by: Andrew Morton 
Signed-off-by: Dave Airlie 
Signed-off-by: Ben Hutchings

fb: rework locking to fix lock ordering on takeover

2013-03-06T03:23:52+00:00

commit 50e244cc793d511b86adea24972f3a7264cae114 upstream.

Adjust the console layer to allow a take over call where the caller
already holds the locks.  Make the fb layer lock in order.

This is partly a band aid, the fb layer is terminally confused about the
locking rules it uses for its notifiers it seems.

[akpm@linux-foundation.org: remove stray non-ascii char, tidy comment]
[akpm@linux-foundation.org: export do_take_over_console()]
[airlied: cleanup another non-ascii char]
Signed-off-by: Alan Cox 
Cc: Florian Tobias Schandinat 
Cc: Stephen Rothwell 
Cc: Jiri Kosina 
Tested-by: Sedat Dilek 
Reviewed-by: Daniel Vetter 
Signed-off-by: Andrew Morton 
Signed-off-by: Dave Airlie 
Signed-off-by: Ben Hutchings

vgacon/vt: clear buffer attributes when we load a 512 character font (v2)

2013-03-06T03:23:50+00:00

commit 2a2483072393b27f4336ab068a1f48ca19ff1c1e upstream.

When we switch from 256->512 byte font rendering mode, it means the
current contents of the screen is being reinterpreted. The bit that holds
the high bit of the 9-bit font, may have been previously set, and thus
the new font misrenders.

The problem case we see is grub2 writes spaces with the bit set, so it
ends up with data like 0x820, which gets reinterpreted into 0x120 char
which the font translates into G with a circumflex. This flashes up on
screen at boot and is quite ugly.

A current side effect of this patch though is that any rendering on the
screen changes color to a slightly darker color, but at least the screen
no longer corrupts.

v2: as suggested by hpa, always clear the attribute space, whether we
are are going to or from 512 chars.

Signed-off-by: Dave Airlie 
Signed-off-by: Ben Hutchings

TTY: Wrong unicode value copied in con_set_unimap()

2012-04-02T16:52:31+00:00

commit 4a4c61b7ce26bfc9d49ea4bd121d52114bad9f99 upstream.

Bugzilla 40012: PIO_UNIMAP bug: error updating Unicode-to-font map
https://bugzilla.kernel.org/show_bug.cgi?id=40012

The unicode font map for the virtual console is a 32x32x64 table which
allocates rows dynamically as entries are added.  The unicode value
increases sequentially and should count all entries even in empty
rows.  The defect is when copying the unicode font map in con_set_unimap(),
the unicode value is not incremented properly.  The wrong unicode value
is entered in the new font map.

Signed-off-by: Liz Clark 
Signed-off-by: Greg Kroah-Hartman

drivers/tty/vt/vt_ioctl.c: fix KDFONTOP 32bit compatibility layer

2012-02-13T19:16:52+00:00

commit cbcb8346054073d000ecac324763372d6abd44ac upstream.

KDFONTOP(GET) currently fails with EIO when being run in a 32bit userland
with a 64bit kernel if the font width is not 8.

This is because of the setting of the KD_FONT_FLAG_OLD flag, which makes
con_font_get return EIO in such case.

This flag should *not* be set for KDFONTOP, since it's actually the whole
point of this flag (see comment in con_font_set for instance).

Signed-off-by: Samuel Thibault 
Reviewed-by: Arnd Bergmann 
Cc: Arthur Taylor 
Cc: Jiri Slaby 
Cc: Jiri Olsa 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

tty: Add export.h for EXPORT_SYMBOL/THIS_MODULE to exporters

2011-10-31T23:31:28+00:00

With module.h being implicitly everywhere via device.h, the absence
of explicitly including something for EXPORT_SYMBOL went unnoticed.
Since we are heading to fix things up and clean module.h from the
device.h file, we need to explicitly include these files now.

Signed-off-by: Paul Gortmaker

keyboard: Do not include

2011-09-22T23:05:08+00:00

The top of  has this comment:

 * Please do not include this file in generic code.  There is currently
 * no requirement for any architecture to implement anything held
 * within this file.
 *
 * Thanks. --rmk

Remove inclusion of , to prevent the following compile error
from happening soon:

| include/linux/irq.h:132: error: redefinition of ‘struct irq_data’
| include/linux/irq.h:286: error: redefinition of ‘struct irq_chip’

drivers/tty/vt/keyboard.c needs to include  for get_irq_regs():

| drivers/tty/vt/keyboard.c:497: error: implicit declaration of function ‘get_irq_regs’
| drivers/tty/vt/keyboard.c:497: warning: initialization makes pointer from integer without a cast

Signed-off-by: Geert Uytterhoeven 
Acked-by: Thomas Gleixner 
Cc: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

tty: clearify structure initializer in notify_write()

2011-08-23T17:48:30+00:00

Even though this is valid C we should not mix C99 initializers with
obfuscated ANSI C. Stick to C99 and initialize c by its name.

Found by clang:
drivers/tty/vt/vt.c:262:55: warning: explicitly assigning a variable of
type 'unsigned int' to itself [-Wself-assign]
    struct vt_notifier_param param = { .vc = vc, unicode = unicode };
                                                 ~~~~~~~ ^ ~~~~~~~

Signed-off-by: Mathias Krause 
Signed-off-by: Greg Kroah-Hartman

TTY: remove tty_locked

2011-08-23T17:34:07+00:00

We used it really only serial and ami_serial. The rest of the
callsites were BUG/WARN_ONs to check if BTM is held. Now that we
pruned tty_locked from both of the real users, we can get rid of
tty_lock along with __big_tty_mutex_owner.

Signed-off-by: Jiri Slaby 
Acked-by: Arnd Bergmann 
Cc: Alan Cox 
Signed-off-by: Greg Kroah-Hartman

Revert "tty: make receive_buf() return the amout of bytes received"

2011-06-03T21:33:24+00:00

This reverts commit b1c43f82c5aa265442f82dba31ce985ebb7aa71c.

It was broken in so many ways, and results in random odd pty issues.

It re-introduced the buggy schedule_work() in flush_to_ldisc() that can
cause endless work-loops (see commit a5660b41af6a: "tty: fix endless
work loop when the buffer fills up").

It also used an "unsigned int" return value fo the ->receive_buf()
function, but then made multiple functions return a negative error code,
and didn't actually check for the error in the caller.

And it didn't actually work at all.  BenH bisected down odd tty behavior
to it:
  "It looks like the patch is causing some major malfunctions of the X
   server for me, possibly related to PTYs.  For example, cat'ing a
   large file in a gnome terminal hangs the kernel for -minutes- in a
   loop of what looks like flush_to_ldisc/workqueue code, (some ftrace
   data in the quoted bits further down).

   ...

   Some more data: It -looks- like what happens is that the
   flush_to_ldisc work queue entry constantly re-queues itself (because
   the PTY is full ?) and the workqueue thread will basically loop
   forver calling it without ever scheduling, thus starving the consumer
   process that could have emptied the PTY."

which is pretty much exactly the problem we fixed in a5660b41af6a.

Milton Miller pointed out the 'unsigned int' issue.

Reported-by: Benjamin Herrenschmidt 
Reported-by: Milton Miller 
Cc: Stefan Bigler 
Cc: Toby Gray 
Cc: Felipe Balbi 
Cc: Greg Kroah-Hartman 
Cc: Alan Cox 
Signed-off-by: Linus Torvalds