kfree on a NULL pointer is a no-op.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
C files should include the header files that prototype their functions.
This keeps the types in sync, and eliminates warnings from GCC
(-Wmissing-prototypes) and Sparse (-Wdecl).
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After commit "TTY: move tty buffers to tty_port", the tty buffers are
not freed in some drivers. This is because tty_port_destructor is not
called whenever a tty_port is freed. This was an assumption I counted
with but was unfortunately untrue. So fix the drivers to fulfil this
assumption.
To be sure, the TTY buffers (and later some stuff) are gone along with
the tty_port, we have to call tty_port_destroy at tear-down places.
This is mostly where the structure containing a tty_port is freed.
This patch does exactly that -- put tty_port_destroy at those places.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There used to be a single tty_ldisc_ref_wait. But then, when a
big-tty-mutex (BTM) was introduced, it has to be tty_ldisc_ref +
tty_unlock + tty_ldisc_ref_wait + tty_lock. Later, BTM was removed
from that path and tty_ldisc_ref + tty_ldisc_ref_wait remained there.
But it makes no sense now. So leave there only tty_ldisc_ref_wait.
And when we have a reference to an ldisc, actually use it in the loop.
Otherwise it may be racy.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cleanups
Clean up compile warnings in kgdboc.c and x86/kernel/kgdb.c
Add module event hooks for simplified debugging with gdb
Fixes
Fix kdb to stop paging with 'q' on bta and dmesg
Fix for data that scrolls off the vga console due to line wrapping
when using the kdb pager
New
The debug core registers for kernel module events which allows a
kernel aware gdb to automatically load symbols and break on entry
to a kernel module
Allow kgdboc=kdb to setup kdb on the vga console
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Merge tag 'for_linus-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb
Pull KGDB/KDB fixes and cleanups from Jason Wessel:
"Cleanups
- Clean up compile warnings in kgdboc.c and x86/kernel/kgdb.c
- Add module event hooks for simplified debugging with gdb
Fixes
- Fix kdb to stop paging with 'q' on bta and dmesg
- Fix for data that scrolls off the vga console due to line wrapping
when using the kdb pager
New
- The debug core registers for kernel module events which allows a
kernel aware gdb to automatically load symbols and break on entry
to a kernel module
- Allow kgdboc=kdb to setup kdb on the vga console"
* tag 'for_linus-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb:
tty/console: fix warnings in drivers/tty/serial/kgdboc.c
kdb,vt_console: Fix missed data due to pager overruns
kdb: Fix dmesg/bta scroll to quit with 'q'
kgdboc: Accept either kbd or kdb to activate the vga + keyboard kdb shell
kgdb,x86: fix warning about unused variable
mips,kgdb: fix recursive page fault with CONFIG_KPROBES
kgdb: Add module event hooks
It is possible to miss data when using the kdb pager. The kdb pager
does not pay attention to the maximum column constraint of the screen
or serial terminal. This result is not incrementing the shown lines
correctly and the pager will print more lines that fit on the screen.
Obviously that is less than useful when using a VGA console where you
cannot scroll back.
The pager will now look at the kdb_buffer string to see how many
characters are printed. It might not be perfect considering you can
output ASCII that might move the cursor position, but it is a
substantially better approximation for viewing dmesg and trace logs.
This also means that the vt screen needs to set the kdb COLUMNS
variable.
Cc: <stable@vger.kernel.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
On some machines using a specific hardware for console screen output,
the update of the pixel frame buffer does not work correctly when
using command line edition. This may be due to a memory cache bug
in the machine on which the problem has been found, but an other
solution is possible.
This patch proposes to avoid touching directly the pixel frame buffer
and to rebuild each character using the standard putc() function
on command line edition.
The resulting code is smaller and not obviously slower (no read
access to the pixel frame buffer).
Tested on a Cubox (ARM Marvell Dove 88AP510 SoC).
Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pm_restore_console() is called from the suspend/resume path, and this
calls vt_move_to_console(), which calls vt_waitactive().
There's a race in this path which causes the process which requests the
suspend to sleep indefinitely waiting for an event which already
happened:
P1 P2
vt_move_to_console()
set_console()
schedule_console_callback()
vt_waitactive()
check n == fg_console +1
console_callback()
switch_screen()
vt_event_post() // no waiters
vt_event_wait() // forever
Fix the race by ensuring we're registered for the event before we check
if it's already completed.
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that we don't have tty->termios tied to drivers->tty we can untangle
the logic here. In addition we can push the removal logic out of the
destructor path.
At that point we can think about sorting out tty_port and console and all
the other ugly hangovers.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We touch the LED from both keyboard callback and direct paths. In
one case we've got the lock held way up the call chain and in the
other we haven't. This leads to complete insanity so fix it by giving
the LED bits their own lock.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This will let us sort out a whole pile of tty related races. The
alternative would be to keep points and refcount the termios objects.
However
1. They are tiny anyway
2. Many devices don't use the stored copies
3. We can remove a pty special case
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are three call sites for this function, and all three
are called within a keyboard handler.
kbd_event_lock is already held within keyboard handlers,
so attempting to lock it in vt_get_leds causes deadlock.
Signed-off-by: Christopher Brannon <chris@the-brannons.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pm_restore_console() is called from the suspend/resume path, and this
calls vt_move_to_console(), which calls vt_waitactive().
There's a race in this path which causes the process which requests the
suspend to sleep indefinitely waiting for an event which already
happened:
P1 P2
vt_move_to_console()
set_console()
schedule_console_callback()
vt_waitactive()
check n == fg_console +1
console_callback()
switch_screen()
vt_event_post() // no waiters
vt_event_wait() // forever
Fix the race by ensuring we're registered for the event before we check
if it's already completed.
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need to initialize the console only on the first open. This is
usually what is done in the ->install hook. vt used to do this in
->open. Now we move it to ->install and use newly added helper for
install: tty_port_install. It ensures tty->port to be set properly.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is identical to tty_schedule_flip. So let us use that instead.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull x86 platform changes from Ingo Molnar:
"This tree includes assorted platform driver updates and a preparatory
series for a platform with custom DMA remapping semantics (sta2x11 I/O
hub)."
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vsmp: Fix number of CPUs when vsmp is disabled
keyboard: Use BIOS Keyboard variable to set Numlock
x86/olpc/xo1/sci: Report RTC wakeup events
x86/olpc/xo1/sci: Produce wakeup events for buttons and switches
x86, platform: Initial support for sta2x11 I/O hub
x86: Introduce CONFIG_X86_DMA_REMAP
x86-32: Introduce CONFIG_X86_DEV_DMA_OPS
Here's the big TTY/serial driver pull request for the 3.5-rc1 merge window.
Nothing major in here, just lots of incremental changes from Alan and
Jiri reworking some tty core things to behave better and to get a more
solid grasp on some of the nasty tty locking issues.
There are a few tty and serial driver updates in here as well.
All of this has been in the linux-next releases for a while with no problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull TTY updates from Greg Kroah-Hartman:
"Here's the big TTY/serial driver pull request for the 3.5-rc1 merge
window.
Nothing major in here, just lots of incremental changes from Alan and
Jiri reworking some tty core things to behave better and to get a more
solid grasp on some of the nasty tty locking issues.
There are a few tty and serial driver updates in here as well.
All of this has been in the linux-next releases for a while with no
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (115 commits)
serial: bfin_uart: Make MMR access compatible with 32 bits bf609 style controller.
serial: bfin_uart: RTS and CTS MMRs can be either 16-bit width or 32-bit width.
serial: bfin_uart: narrow the reboot condition in DMA tx interrupt
serial: bfin_uart: Adapt bf5xx serial driver to bf60x serial4 controller.
Revert "serial_core: Update buffer overrun statistics."
tty: hvc_xen: NULL dereference on allocation failure
tty: Fix LED error return
tty: Allow uart_register/unregister/register
tty: move global ldisc idle waitqueue to the individual ldisc
serial8250-em: Add DT support
serial8250-em: clk_get() IS_ERR() error handling fix
serial_core: Update buffer overrun statistics.
tty: drop the pty lock during hangup
cris: fix missing tty arg in wait_event_interruptible_tty call
tty/amiserial: Add missing argument for tty_unlock()
tty_lock: Localise the lock
pty: Lock the devpts bits privately
tty_lock: undo the old tty_lock use on the ctty
serial8250-em: Emma Mobile UART driver V2
Add missing call to uart_update_timeout()
...
3.4-rc introduced a regression when setting the LEDS. We do the right thing
but then return an error code.
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=43144
Reported-by: Christian Casteyde
Signed-off-by: Alan Cox <alan@linux/intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
3.4-rc introduced a regression when setting the LEDS. We do the right thing
but then return an error code.
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=43144
Reported-by: Christian Casteyde
Signed-off-by: Alan Cox <alan@linux/intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The PC BIOS does provide a NUMLOCK flag containing the desired state
of this LED. This patch sets the current state according to the data
in the bios.
[ hpa: fixed __weak declaration without definition, changed "inline"
to "static inline" ]
Signed-Off-By: Joshua Cov <joshuacov@googlemail.com>
Link: http://lkml.kernel.org/r/CAKL7Q7rvq87TNS1T_Km8fW_5OzS%2BSbYazLXKxW-6ztOxo3zorg@mail.gmail.com
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Fixing the locking accidentally replaced a race in the scroll
lock handling with a deadlock. Turn it back into a race for
now.
The basic problem is that there are two paths into the tty
stop/start helpers. One via the tty layer ^S/^Q handling
where we need to take the kbd_event_lock and one via the
special keyboard handler for fn_hold where we already hold
it. Probably we need to split out into a separate LED lock
but for now just go back to the race as it's a bit close
to release.
Reported-by: Clemens Ladisch <clemens@ladisch.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we do this it becomes clear the lock we should be holding is the vc
lock, and in fact many of our other helpers are properly invoked this way.
We don't at this point guarantee not to race the keyboard code but the results
of that appear harmless and that was true before we started as well.
We now have no users of tty_lock in the console driver...
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
set_get_cmap() ignored the result of {get,put}_user(), causing ioctl(vt,
{G,P}IO_CMAP, 0xdeadbeef) to silently fail.
Another side effect of this: calling the PIO_CMAP ioctl with an invalid
buffer would zero the default colormap and the palette for all vts (all
colors set to black).
Leave the default colormap intact and return -EFAULT when
reading/writing to the userspace buffer fails.
Signed-off-by: Michael Gehring <mg@ebfe.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A prototype for kmsg records instead of a byte-stream buffer revealed
a couple of missing printk(KERN_CONT ...) uses. Subsequent calls produce
one record per printk() call, while all should have ended up in a single
record.
Instead of:
ACPI: (supports S0 S5)
ACPI: PCI Interrupt Link [LNKA] (IRQs 5 *10 11)
hpet0: at MMIO 0xfed00000, IRQs 2 , 8 , 0
It prints:
ACPI: (supports S0
S5
)
ACPI: PCI Interrupt Link [LNKA] (IRQs
5
*10
11
)
hpet0: at MMIO 0xfed00000, IRQs
2
, 8
, 0
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove all #inclusions of asm/system.h preparatory to splitting and killing
it. Performed with the following command:
perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: David Howells <dhowells@redhat.com>
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 <liz.clark@hp.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We forgot to set the "key_map" variable here, so it's still NULL. This
was introduced recently in 079c9534a9 "vt:tackle kbd_table".
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All num, magic and owner are set by alloc_tty_driver. No need to
re-set them on each allocation site.
pti driver sets something different to what it passes to
alloc_tty_driver. It is not a bug, since we don't use the lines
parameter in any way. Anyway this is fixed, and now we do the right
thing.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We leave the existing paste mess alone and just fix up the vt side of
things.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some of this ventures into selection which is still a complete lost cause. We
are not making it any worse. It's completely busted anyway.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At this point we have the tty_lock guarding a couple of oddities, plus the
translation and unimap still.
We also extend the console_lock in a couple of spots where coverage is wrong
and switch vcs_open to use the right lock !
[Fixed the locking issue Jiri reported]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The font methods are console_lock covered. Unfortunately they don't extend
the lock over all the needed tests.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Keyboard struct lifetime is easy, but the locking is not and is completely
ignored by the existing code. Tackle this one head on
- Make the kbd_table private so we can run down all direct users
- Hoick the relevant ioctl handlers into the keyboard layer
- Lock them with the keyboard lock so they don't change mid keypress
- Add helpers for things like console stop/start so we isolate the poking
around properly
- Tweak the braille console so it still builds
There are a couple of FIXME locking cases left for ioctls that are so hideous
they should be addressed in a later patch. After this patch the kbd_table is
private and all the keyboard jiggery pokery is in one place.
This update fixes speakup and also a memory leak in the original.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
First step to debletcherising the vt console layer - pick a victim and fix
the locking
This is a nice simple object with its own rules so lets pick it out for
treatment. The user of the table already has a lock so we will also use the
same lock for updates.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 <samuel.thibault@ens-lyon.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Arthur Taylor <art@ified.ca>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <paul.gortmaker@windriver.com>
The top of <linux/irq.h> 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 <linux/irq.>, 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 <asm/irq_regs.h> 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 <geert@linux-m68k.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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 <minipli@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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 <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This reverts commit b1c43f82c5.
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 a5660b41af: "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 a5660b41af.
Milton Miller pointed out the 'unsigned int' issue.
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reported-by: Milton Miller <miltonm@bga.com>
Cc: Stefan Bigler <stefan.bigler@keymile.com>
Cc: Toby Gray <toby.gray@realvnc.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
it makes it simpler to keep track of the amount of
bytes received and simplifies how flush_to_ldisc counts
the remaining bytes. It also fixes a bug of lost bytes
on n_tty when flushing too many bytes via the USB
serial gadget driver.
Tested-by: Stefan Bigler <stefan.bigler@keymile.com>
Tested-by: Toby Gray <toby.gray@realvnc.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Traditional \E[2J sequence erases console display but scroll-back
buffer and underlying device (frame) buffer keep data that can be
accessed by scrolling console back.
This patch introduce new \E[J parameter 3 that allows to scramble
scroll-back buffer explicitly. Session locking programs (screen,
vlock) can use it to prevent attacker to browse locked console
history.
Signed-off-by: Petr Písař <ppisar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
remove invalid location line in each file header after location
moved from driver/char to driver/tty
Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/tty/vt/vt.c:892:2: warning: Value stored to 'old_screen_size' is never read
old_screen_size = vc->vc_screenbuf_size;
^ ~~~~~~~~~~~~~~~~~~~~~
drivers/tty/vt/vt.c:890:2: warning: Value stored to 'old_cols' is never read
old_cols = vc->vc_cols;
^ ~~~~~~~~~~~
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
