Commit Graph

128 Commits

Author SHA1 Message Date
Nicolas Pitre 19e3ae6b4f vt: provide notifications on selection changes
The vcs device's poll/fasync support relies on the vt notifier to signal
changes to the screen content.  Notifier invocations were missing for
changes that comes through the selection interface though.  Fix that.

Tested with BRLTTY 5.2.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Cc: Dave Mielke <dave@mielke.cc>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02 10:09:54 -08:00
Imre Deak 4c215fe8e2 vt: fix locking around vt_bind/vt_unbind
Currently vt_bind and vt_unbind access at least the con_driver object
and registered_con_driver array without holding the console lock. Fix
this by locking around the whole function in each case.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09 14:39:52 -08:00
Imre Deak 2cf30f752c vt: fix check for system/busy console drivers when unregistering them
The default console driver (conswitchp) and busy drivers bound to a
console (as reported by con_is_bound()) shouldn't be unregistered.
System console drivers (without the CON_DRIVER_FLAG_MODULE flag) can be
unregistered, provided they are neither default nor busy. The current
code checks for the CON_DRIVER_FLAG_INIT flag but this doesn't make
sense: this flag is set for a driver whenever its associated console's
con_startup() function is called, which first happens when the console
driver is registered (so before the console gets bound) and gets cleared
when the console gets unbound. The purpose of this flag is to show if we
need to call con_startup() on a console before we use it.

Based on the above, do_unregister_con_driver() in its current form will
allow unregistering a console driver only if it was never bound, but
will refuse to unregister one that was bound and later unbound.

Fix this by dropping the CON_DRIVER_FLAG_INIT check, allowing
unregistering of any console driver provided that it's not the default
one and it's not busy.

v2:
- reword the third paragraph to clarify how the fix works (Peter Hurley)
v3:
- unchanged
v4:
- Allow unregistering a system console driver too, needed by i915 to
  unregister vgacon. Update commit description accordingly. (Daniel)

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09 14:39:52 -08:00
Joe Perches e620e54884 tty: pr_warning->pr_warn and logging neatening
Convert the pr_warning to the more common pr_warn.

Other miscellanea:

o Convert unusual PR_FMT define and uses to pr_fmt
o Remove unnecessary OOM message
o Fix grammar in an error message
o Convert a pr_warning with a KERN_ERR to pr_err

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-25 17:06:38 -08:00
Peter Hurley 52c40fca1a vt: Fix build breakage when !CONFIG_VT_CONSOLE
Commit 68952076e9 ("vt: Remove
vt_get_kmsg_redirect() from uapi header") fails to compile if
!CONFIG_VT_CONSOLE.

Move macro definition for vt_get_kmsg_redirect() up with file-scope
function declarations.

Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-22 07:48:51 -08:00
Greg Kroah-Hartman 394e849b83 Merge 3.18-rc4 into tty-next.
This resolves a merge issue with drivers/tty/serial/8250/8250_mtk.c

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-10 12:42:04 +09:00
Peng Fan 085f4d8413 tty:vt remove obsolete struct initializer
This patch fixes sparse warning:
"obsolete struct initializer, use C99 syntax"

Signed-off-by: Peng Fan <van.freenix@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 20:22:47 -08:00
Peter Hurley 68952076e9 vt: Remove vt_get_kmsg_redirect() from uapi header
vt_get_kmsg_redirect() only has meaning to the console driver as
an alias for calling vt_kmsg_redirect(). Move the macro definition
to the only source file which uses it; remove from uapi/linux/vt.h

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 20:18:30 -08:00
Imre Deak 9e326f7871 tty/vt: don't set font mappings on vc not supporting this
We can call this function for a dummy console that doesn't support
setting the font mapping, which will result in a null ptr BUG. So check
for this case and return error for consoles w/o font mapping support.

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=59321
Signed-off-by: Imre Deak <imre.deak@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 20:12:02 -08:00
Mark Rustad 9d329c1c68 tty/vt/keyboard: Resolve many shadow warnings
Many local variables were given the same name as a global. This
is valid, but generates many shadow warnings in W=2 builds. Resolve
them by changing the local names. Also change local variables
named "up" because they shadow the semaphore "up" function. Also
moved the outer declaration of the variable "a" because it is
only used in one block, and that resolves all of the shadow warnings
for the other declarations of "a" that have different types.

Change diacr => dia, kbd => kb, rep => rpt, up => udp.

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-08 16:30:43 -07:00
Dave Airlie 884d6147ba Merge tag 'drm-intel-fixes-2014-06-17' of git://anongit.freedesktop.org/drm-intel into drm-next
First round of fixes for 3.16-rc, mostly cc: stable, and the vt/vgacon
fixes from Daniel [1] to avoid hangs and unclaimed register errors on
module load/reload.

* tag 'drm-intel-fixes-2014-06-17' of git://anongit.freedesktop.org/drm-intel:
  drm/i915/bdw: remove erroneous chv specific workarounds from bdw code
  drm/i915: fix possible refcount leak when resetting forcewake
  drm/i915: Reorder semaphore deadlock check
  drm/i95: Initialize active ring->pid to -1
  drm/i915: set backlight duty cycle after backlight enable for gen4
  drm/i915: Avoid div-by-zero when pixel_multiplier is zero
  drm/i915: Disable FBC by default also on Haswell and later
  drm/i915: Kick out vga console
  drm/i915: Fixup global gtt cleanup
  vt: Don't ignore unbind errors in vt_unbind
  vt: Fix up unregistration of vt drivers
  vt: Fix replacement console check when unbinding
2014-06-19 10:54:35 +10:00
Daniel Vetter f418f2ec44 vt: Don't ignore unbind errors in vt_unbind
Otherwise the loop will never stop since we don't make any
forward progress. Noticed while breaking this accidentally
in a painful attempt to make vga_con unregistering work.

With this patch we'll bail out on the first attempt, which
at least leaves a useful enough system behind for debugging.
Livelocks on console_lock just aren't fun.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-06-06 22:19:47 +02:00
Daniel Vetter d9c660e750 vt: Fix up unregistration of vt drivers
A bunch of issues:
- We should not kick out the default console (which is tracked in
  conswitchp), so check for that.
- Add better error codes so callers can differentiate between "something
  went wrong" and "your driver isn't registered already". i915 needs
  that so it doesn't fall over when reloading the driver and hence
  vga_con is already unregistered.
- There's a mess with the driver flags: What we need to check for is
  that the driver isn't used any more, i.e. unbound completely (FLAG_INIT).
  And not whether it's the boot console or not (which is the only one
  which doesn't have FLAG_MODULE). Otherwise there's no way to kick
  out the boot console, which i915 wants to do to prevent havoc with
  vga_con interferring (which tends to hang machines).

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-06-06 22:19:32 +02:00
Daniel Vetter 249f7b3e13 vt: Fix replacement console check when unbinding
I don't fully understand the magic of the vt register/unregister
logic, but apparently everything but the inital console (as set
in the conswitchp pointer) is marked with FLAG_MODULE. Which means
if something unregistered the boot vt driver (e.g. i915.ko kicking
out vga_con) there's nothing left when trying to unbind e.g. fbcon
through sysfs.

But in most cases have the dummy console hanging around besides the
boot console, so this test is fairly dubious. What we actually want is
simply a different console than the one we want to unbind.

v2: Correct the commit message to clarify that the dummy console isn't
always around, but only in most cases (David).

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-06-06 22:18:25 +02:00
Takashi Iwai 91727b16d5 console: Remove superfluous readonly check
uni_pagedir.readonly is never set.  Let's get rid of superfluous check
codes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 13:37:21 -07:00
Takashi Iwai e4bdab70dd console: Use explicit pointer type for vc_uni_pagedir* fields
The vc_data.vc_uni_pagedir filed is currently long int, supposedly to
be served generically.  This, however, leads to lots of cast to
pointer, and rather it worsens the readability significantly.

Actually, we have now only a single uni_pagedir map implementation,
and this won't change likely.  So, it'd be much more simple and
error-prone to just use the exact pointer for struct uni_pagedir
instead of long.

Ditto for vc_uni_pagedir_loc.  It's a pointer to the uni_pagedir, thus
it can be changed similarly to the exact type.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 13:37:21 -07:00
Adam Borowski cec5b2a97a vt: emulate 8- and 24-bit colour codes.
Most other mainstream terminals support "xterm256" colours, which means
people sometimes use these blindly without checking capabilities.

Because of hardware limitations of VGA consoles, colours are downgraded to
16 foregrounds and 8 backgrounds.  On fbdev consoles it would be possible
to support them without quality loss, but adding that would require quite a
large amount of code.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28 13:14:08 -07:00
Adam Borowski 63f3a16db9 vt: detect and ignore OSC codes.
These can be used to send commands consisting of an arbitrary string to the
terminal, most often used to set a terminal's window title or to redefine
the colour palette.  Our console doesn't use OSC, unlike everything else,
which can lead to junk being displayed if a process sends such a code
unconditionally.

The rules for termination follow established practice rather than Ecma-48.
Ecma-48 requires the string to use only byte values 0x08..0x0D and
0x20..0x7E, terminated with either ESC \ or 0x9C.  This would disallow using
8-bit characters, which are reasonable for example in window titles.
A widespread idiom is to terminate with 0x07.  The behaviour for other
control characters differs between terminal emulators, I followed libvte and
xterm:
* 0x07 and ESC anything terminate
* nothing else terminates, all 8-bit values including 0x9C are considered a
  part of the string

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-28 16:25:47 -08:00
Adam Borowski b290af68de vt: drop an useless enum and assignment.
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-28 16:25:47 -08:00
Petr Písař 0930b0950a vt: Fix secure clear screen
\E[3J console code (secure clear screen) needs to update_screen(vc)
in order to write-through blanks into off-screen video memory.

This has been removed accidentally in 3.6 by:

commit 81732c3b2f
Author: Jean-François Moine <moinejf@free.fr>
Date:   Thu Sep 6 19:24:13 2012 +0200

    tty vt: Fix line garbage in virtual console on command line edition

Signed-off-by: Petr Písař <petr.pisar@atlas.cz>
Cc: stable <stable@vger.kernel.org> # 3.6
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-13 11:12:00 -08:00
Adam Borowski 3415097ff0 vt: properly ignore xterm-256 colour codes
This is not a bug on our side, but a misdesign in ITU T.416, yet with
all popular terminals supporting these codes, people consider this to
be a bug in Linux.  By breaking the design principles behind SGR codes
(gracefully ignoring unsupported ones should not require knowing about
them), 256 colour ones tend to turn blinking on before invoking an
arbitrary unrelated command.

This commit doesn't add such support, merely skips such codes without
ill effects.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26 15:58:27 -07:00
Adam Borowski 6454588092 vt: break a couple of obsolete SCOish codes.
No modern terminal supports them, and SGR 38 conflicts with detecting
xterm-256 colours.  This also makes SGR 39 consistent with other popular
terminals.  Neither are used by ncurses' terminfo.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26 15:58:26 -07:00
Clemens Ladisch 3855ae1c48 vt: make the default color configurable
The virtual console has (undocumented) module parameters to set the
colors for italic and underlined text, but the default text color was
hardcoded for some reason.  This made it impossible to change the color
for startup messages, or to set the default for new virtual consoles.
Add a module parameter for that, and document the entire bunch.

Any hacker who thinks that a command prompt on a "black screen with
white font" is not supicious enough can now use the kernel parameter
vt.color=10 to get a nice, evil green.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-05 15:06:46 +08:00
Andreas Platschek cf940ebe98 tty: Remove dead code
-> The ledptrs[] array is never initialized.
-> There is no place where kbd->ledmode is set to LED_SHOW_MEM therefore the if
   statement does not make much sense.
-> Since LED_SHOW_MEM is not used, it can be removed from the header file as well.

Signed-off-by: Andreas Platschek <andi.platschek@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 16:19:48 -07:00
Peter Hurley a7c8d58c79 tty: Fix unsafe vt paste_selection()
Convert the tty_buffer_flush() exclusion mechanism to a
public interface - tty_buffer_lock/unlock_exclusive() - and use
the interface to safely write the paste selection to the line
discipline.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-23 16:47:10 -07:00
Peter Hurley 6a1c0680cf tty: Convert termios_mutex to termios_rwsem
termios is commonly accessed unsafely (especially by N_TTY)
because the existing mutex forces exclusive access.
Convert existing usage.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-23 16:43:01 -07:00
Peter Hurley 24a89d1cb6 tty: Make ldisc input flow control concurrency-friendly
Although line discipline receiving is single-producer/single-consumer,
using tty->receive_room to manage flow control creates unnecessary
critical regions requiring additional lock use.

Instead, introduce the optional .receive_buf2() ldisc method which
returns the # of bytes actually received. Serialization is guaranteed
by the caller.

In turn, the line discipline should schedule the buffer work item
whenever space becomes available; ie., when there is room to receive
data and receive_room() previously returned 0 (the buffer work
item stops processing if receive_buf2() returns 0). Note the
'no room' state need not be atomic despite concurrent use by two
threads because only the buffer work thread can set the state and
only the read() thread can clear the state.

Add n_tty_receive_buf2() as the receive_buf2() method for N_TTY.
Provide a public helper function, tty_ldisc_receive_buf(), to use
when directly accessing the receive_buf() methods.

Line disciplines not using input flow control can continue to set
tty->receive_room to a fixed value and only provide the receive_buf()
method.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-23 16:42:59 -07:00
Linus Torvalds 790eac5640 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull second set of VFS changes from Al Viro:
 "Assorted f_pos race fixes, making do_splice_direct() safe to call with
  i_mutex on parent, O_TMPFILE support, Jeff's locks.c series,
  ->d_hash/->d_compare calling conventions changes from Linus, misc
  stuff all over the place."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  Document ->tmpfile()
  ext4: ->tmpfile() support
  vfs: export lseek_execute() to modules
  lseek_execute() doesn't need an inode passed to it
  block_dev: switch to fixed_size_llseek()
  cpqphp_sysfs: switch to fixed_size_llseek()
  tile-srom: switch to fixed_size_llseek()
  proc_powerpc: switch to fixed_size_llseek()
  ubi/cdev: switch to fixed_size_llseek()
  pci/proc: switch to fixed_size_llseek()
  isapnp: switch to fixed_size_llseek()
  lpfc: switch to fixed_size_llseek()
  locks: give the blocked_hash its own spinlock
  locks: add a new "lm_owner_key" lock operation
  locks: turn the blocked_list into a hashtable
  locks: convert fl_link to a hlist_node
  locks: avoid taking global lock if possible when waking up blocked waiters
  locks: protect most of the file_lock handling with i_lock
  locks: encapsulate the fl_link list handling
  locks: make "added" in __posix_lock_file a bool
  ...
2013-07-03 09:10:19 -07:00
Al Viro 65004276fc vc: switch to fixed_size_llseek()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:30 +04:00
Greg Kroah-Hartman 805bf3daf3 Merge 3.10-rc7 into tty-next
We want the tty fixes in this branch as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-24 15:17:53 -07:00
Ross Lagerwall ef223fb3d1 tty/vt: Return EBUSY if deallocating VT1 and it is busy
Commit 421b40a628 ("tty/vt: Fix vc_deallocate() lock order") changed
the behavior when deallocating VT 1.  Previously if trying to
deallocate VT1 and it is busy, we would return EBUSY.  The commit
changed this to return 0 (success).

This commit restores the old behavior.

Signed-off-by: Ross Lagerwall <rosslagerwall@gmail.com>
Tested-by: Mikael Pettersson <mikpe@it.uu.se>
Acked-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17 12:37:29 -07:00
Greg Kroah-Hartman 8095e4e81b Merge 3.10-rc3 into tty-next
We want these fixes.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-27 10:57:53 +09:00
Wang YanQing 155957f56c TTY:vt: convert remain take_over_console's users to do_take_over_console
Impact:
1:convert all remain take_over_console to do_take_over_console
2:update take_over_console to do_take_over_console in comment

Commit dc9641895a ("vt: delete unneeded functions
register_con_driver|take_over_console") delete take_over_console,
but forget to convert remain take_over_console's users to new API
do_take_over_console, this patch fix it.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 22:29:27 -07:00
Wang YanQing 50539dd4f8 vt: delete unneeded function unregister_con_driver
Now there is no place use unregister_con_driver,
and we can achieve unregister_con_driver's function
with unregister_con_driver easily, so just delete it
to reduce code size and duplication.

Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 12:27:59 -07:00
Wang YanQing 70125e76b0 fbcon: convert last two unregister_con_driver call to do_unregister_con_driver
There are only two place use unregister_con_driver now, this patch
convert them to do_unregister_con_driver too, then we can delete
unregister_con_driver whos function can be achieved with do_unregister_con_driver
easily to reduce code size and duplication.

Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 12:27:59 -07:00
Wang YanQing 77d6c98454 vt: delete unneeded function bind_con_driver
Now there is no place use bind_con_driver,
and do_bind_con_driver can achieve bind_con_driver's
function easily, so just delete it to reduce code size and
duplication.

Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 12:27:59 -07:00
Wang YanQing c62a1e57e4 vt: convert last bind_con_driver call to do_bind_con_driver
There is only one place use bind_con_driver now, this patch
convert it to do_bind_con_driver too, then we can delete
bind_con_driver whos function can be replaced by do_bind_con_driver
easily to reduce code size and duplication.

Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 12:27:59 -07:00
Wang YanQing c1f5e38a5d vt: delete unneeded function unbind_con_driver
Now there is no place use unbind_con_driver,
and we can achieve unbind_con_driver's function
with do_unbind_con_driver easily, so just delete
it to reduce code size and duplication.

Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 12:27:59 -07:00
Wang YanQing 618f2b9007 vt: convert last unbind_con_driver call to do_unbind_con_driver
There is only one place use unbind_con_driver, this patch
convert it to do_unbind_con_driver too, then we can delete
unbind_con_driver to reduce code size and duplication.

Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 12:27:58 -07:00
Wang YanQing dc9641895a vt: delete unneeded functions register_con_driver|take_over_console
Now there is no place use register_con_driver|take_over_console,
and we can achieve their function with do_register_con_driver|
do_take_over_console easily, so just delete them to reduce code duplication.

Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 12:27:58 -07:00
Peter Hurley 421b40a628 tty/vt: Fix vc_deallocate() lock order
Now that the tty port owns the flip buffers and i/o is allowed
from the driver even when no tty is attached, the destruction
of the tty port (and the flip buffers) must ensure that no
outstanding work is pending.

Unfortunately, this creates a lock order problem with the
console_lock (see attached lockdep report [1] below).

For single console deallocation, drop the console_lock prior
to port destruction. When multiple console deallocation,
defer port destruction until the consoles have been
deallocated.

tty_port_destroy() is not required if the port has not
been used; remove from vc_allocate() failure path.

[1] lockdep report from Dave Jones <davej@redhat.com>

 ======================================================
 [ INFO: possible circular locking dependency detected ]
 3.9.0+ #16 Not tainted
 -------------------------------------------------------
 (agetty)/26163 is trying to acquire lock:
 blocked:  ((&buf->work)){+.+...}, instance: ffff88011c8b0020, at: [<ffffffff81062065>] flush_work+0x5/0x2e0

 but task is already holding lock:
 blocked:  (console_lock){+.+.+.}, instance: ffffffff81c2fde0, at: [<ffffffff813bc201>] vt_ioctl+0xb61/0x1230

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (console_lock){+.+.+.}:
        [<ffffffff810b3f74>] lock_acquire+0xa4/0x210
        [<ffffffff810416c7>] console_lock+0x77/0x80
        [<ffffffff813c3dcd>] con_flush_chars+0x2d/0x50
        [<ffffffff813b32b2>] n_tty_receive_buf+0x122/0x14d0
        [<ffffffff813b7709>] flush_to_ldisc+0x119/0x170
        [<ffffffff81064381>] process_one_work+0x211/0x700
        [<ffffffff8106498b>] worker_thread+0x11b/0x3a0
        [<ffffffff8106ce5d>] kthread+0xed/0x100
        [<ffffffff81601cac>] ret_from_fork+0x7c/0xb0

 -> #0 ((&buf->work)){+.+...}:
        [<ffffffff810b349a>] __lock_acquire+0x193a/0x1c00
        [<ffffffff810b3f74>] lock_acquire+0xa4/0x210
        [<ffffffff810620ae>] flush_work+0x4e/0x2e0
        [<ffffffff81065305>] __cancel_work_timer+0x95/0x130
        [<ffffffff810653b0>] cancel_work_sync+0x10/0x20
        [<ffffffff813b8212>] tty_port_destroy+0x12/0x20
        [<ffffffff813c65e8>] vc_deallocate+0xf8/0x110
        [<ffffffff813bc20c>] vt_ioctl+0xb6c/0x1230
        [<ffffffff813b01a5>] tty_ioctl+0x285/0xd50
        [<ffffffff811ba825>] do_vfs_ioctl+0x305/0x530
        [<ffffffff811baad1>] sys_ioctl+0x81/0xa0
        [<ffffffff81601d59>] system_call_fastpath+0x16/0x1b

 other info that might help us debug this:

 [ 6760.076175]  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(console_lock);
                                lock((&buf->work));
                                lock(console_lock);
   lock((&buf->work));

  *** DEADLOCK ***

 1 lock on stack by (agetty)/26163:
  #0: blocked:  (console_lock){+.+.+.}, instance: ffffffff81c2fde0, at: [<ffffffff813bc201>] vt_ioctl+0xb61/0x1230
 stack backtrace:
 Pid: 26163, comm: (agetty) Not tainted 3.9.0+ #16
 Call Trace:
  [<ffffffff815edb14>] print_circular_bug+0x200/0x20e
  [<ffffffff810b349a>] __lock_acquire+0x193a/0x1c00
  [<ffffffff8100a269>] ? sched_clock+0x9/0x10
  [<ffffffff8100a269>] ? sched_clock+0x9/0x10
  [<ffffffff8100a200>] ? native_sched_clock+0x20/0x80
  [<ffffffff810b3f74>] lock_acquire+0xa4/0x210
  [<ffffffff81062065>] ? flush_work+0x5/0x2e0
  [<ffffffff810620ae>] flush_work+0x4e/0x2e0
  [<ffffffff81062065>] ? flush_work+0x5/0x2e0
  [<ffffffff810b15db>] ? mark_held_locks+0xbb/0x140
  [<ffffffff8113c8a3>] ? __free_pages_ok.part.57+0x93/0xc0
  [<ffffffff810b15db>] ? mark_held_locks+0xbb/0x140
  [<ffffffff810652f2>] ? __cancel_work_timer+0x82/0x130
  [<ffffffff81065305>] __cancel_work_timer+0x95/0x130
  [<ffffffff810653b0>] cancel_work_sync+0x10/0x20
  [<ffffffff813b8212>] tty_port_destroy+0x12/0x20
  [<ffffffff813c65e8>] vc_deallocate+0xf8/0x110
  [<ffffffff813bc20c>] vt_ioctl+0xb6c/0x1230
  [<ffffffff810aec41>] ? lock_release_holdtime.part.30+0xa1/0x170
  [<ffffffff813b01a5>] tty_ioctl+0x285/0xd50
  [<ffffffff812b00f6>] ? inode_has_perm.isra.46.constprop.61+0x56/0x80
  [<ffffffff811ba825>] do_vfs_ioctl+0x305/0x530
  [<ffffffff812b04db>] ? selinux_file_ioctl+0x5b/0x110
  [<ffffffff811baad1>] sys_ioctl+0x81/0xa0
  [<ffffffff81601d59>] system_call_fastpath+0x16/0x1b

Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 12:15:59 -07:00
Greg Kroah-Hartman ef99f3aee9 Merge 3.9-rc5 into tty-next
We need the fixes here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-01 12:01:10 -07:00
Al Viro e8cd81693b vt: synchronize_rcu() under spinlock is not nice...
vcs_poll_data_free() calls unregister_vt_notifier(), which calls
atomic_notifier_chain_unregister(), which calls synchronize_rcu().
Do it *after* we'd dropped ->f_lock.

Cc: stable@vger.kernel.org (all kernels since 2.6.37)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-26 20:30:17 -04:00
Zhang Yanfei 8358f6242d driver: tty: vt: remove cast for kmalloc return value
remove cast for kmalloc return value.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-18 17:09:37 -07:00
Linus Torvalds d895cb1af1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile (part one) from Al Viro:
 "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
  locking violations, etc.

  The most visible changes here are death of FS_REVAL_DOT (replaced with
  "has ->d_weak_revalidate()") and a new helper getting from struct file
  to inode.  Some bits of preparation to xattr method interface changes.

  Misc patches by various people sent this cycle *and* ocfs2 fixes from
  several cycles ago that should've been upstream right then.

  PS: the next vfs pile will be xattr stuff."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
  saner proc_get_inode() calling conventions
  proc: avoid extra pde_put() in proc_fill_super()
  fs: change return values from -EACCES to -EPERM
  fs/exec.c: make bprm_mm_init() static
  ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
  ocfs2: fix possible use-after-free with AIO
  ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
  get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
  target: writev() on single-element vector is pointless
  export kernel_write(), convert open-coded instances
  fs: encode_fh: return FILEID_INVALID if invalid fid_type
  kill f_vfsmnt
  vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
  nfsd: handle vfs_getattr errors in acl protocol
  switch vfs_getattr() to struct path
  default SET_PERSONALITY() in linux/elf.h
  ceph: prepopulate inodes only when request is aborted
  d_hash_and_lookup(): export, switch open-coded instances
  9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
  9p: split dropping the acls from v9fs_set_create_acl()
  ...
2013-02-26 20:16:07 -08:00
Linus Torvalds fffddfd6c8 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull drm merge from Dave Airlie:
 "Highlights:

   - TI LCD controller KMS driver

   - TI OMAP KMS driver merged from staging

   - drop gma500 stub driver

   - the fbcon locking fixes

   - the vgacon dirty like zebra fix.

   - open firmware videomode and hdmi common code helpers

   - major locking rework for kms object handling - pageflip/cursor
     won't block on polling anymore!

   - fbcon helper and prime helper cleanups

   - i915: all over the map, haswell power well enhancements, valleyview
     macro horrors cleaned up, killing lots of legacy GTT code,

   - radeon: CS ioctl unification, deprecated UMS support, gpu reset
     rework, VM fixes

   - nouveau: reworked thermal code, external dp/tmds encoder support
     (anx9805), fences sleep instead of polling,

   - exynos: all over the driver fixes."

Lovely conflict in radeon/evergreen_cs.c between commit de0babd60d
("drm/radeon: enforce use of radeon_get_ib_value when reading user cmd")
and the new changes that modified that evergreen_dma_cs_parse()
function.

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (508 commits)
  drm/tilcdc: only build on arm
  drm/i915: Revert hdmi HDP pin checks
  drm/tegra: Add list of framebuffers to debugfs
  drm/tegra: Fix color expansion
  drm/tegra: Split DC_CMD_STATE_CONTROL register write
  drm/tegra: Implement page-flipping support
  drm/tegra: Implement VBLANK support
  drm/tegra: Implement .mode_set_base()
  drm/tegra: Add plane support
  drm/tegra: Remove bogus tegra_framebuffer structure
  drm: Add consistency check for page-flipping
  drm/radeon: Use generic HDMI infoframe helpers
  drm/tegra: Use generic HDMI infoframe helpers
  drm: Add EDID helper documentation
  drm: Add HDMI infoframe helpers
  video: Add generic HDMI infoframe helpers
  drm: Add some missing forward declarations
  drm: Move mode tables to drm_edid.c
  drm: Remove duplicate drm_mode_cea_vic()
  gma500: Fix n, m1 and m2 clock limits for sdvo and lvds
  ...
2013-02-25 16:46:44 -08:00
Nicolas Pitre a883b70d8e tty vt: fix character insertion overflow
Commit 81732c3b2f ("tty vt: Fix line garbage in virtual console on
command line edition") broke insert_char() in multiple ways.  Then
commit b1a925f44a ("tty vt: Fix a regression in command line edition")
partially fixed it.  However, the buffer being moved is still too large
and overflowing beyond the end of the current line, corrupting existing
characters on the next line.

Example test case:

echo -e "abc\nde\x1b[A\x1b[4h \x1b[4l\x1b[B"

Expected result:

ab c
de

Current result:

ab c
 e

Needless to say that this is very annoying when inserting words in the
middle of paragraphs with certain text editors.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Cc: Jean-François Moine <moinejf@free.fr>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-24 17:29:49 -08:00
Al Viro 496ad9aa8e new helper: file_inode(file)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:31 -05:00
Dave Airlie 62cd2fa82a Merge branch 'console-fixes' into drm-next
(not the fbcon maintainer pull 2)

fix bug in vgacon on bootup and fbcon losing fonts on startup.

* console-fixes: (50 commits)
  fbcon: don't lose the console font across generic->chip driver switch
  vgacon/vt: clear buffer attributes when we load a 512 character font (v2)
2013-02-08 12:13:43 +10:00
Takashi Iwai e93a9a8687 fb: Yet another band-aid for fixing lockdep mess
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 <tiwai@suse.de>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: stable <stable@vger.kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-02-08 12:02:41 +10:00