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>
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>
(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)
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>
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.
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
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>
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>
Don't force output if you intend to reboot immediately.
In this patch, I'm disabling the functionality enabled by
vc->vc_panic_force_write if panic_timeout < 0 (i.e. no timeout).
vc_panic_force_write is only enabled for fb video consoles if the
FBINFO_CAN_FORCE_OUTPUT flag is set.
For our application, we're using ram_oops to preserved the panic in
memory. We want to reliably, and as fast as possible, machine_restart.
The vc_panic_force_write flag results in a bunch of graphics driver code
to be invoked which slows down restart and decreases reliability. Since
we're already storing the panic in RAM and are going to reboot
immediately, there is no benefit in mode switching back to the vc in
order to display the panic output. The log buffer will get flushed by
the console_unblank() call so remote management consoles should see all
output.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Olaf Hering <olaf@aepfle.de>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
seems there's no longer need for using con_buf/conf_buf_mtx
as vcs_read/vcs_write buffer for user's data.
The do_con_write function, that was the other user of this,
is currently using its own kmalloc-ed buffer.
Not sure when this got changed, as I was able to find this code
in 2.6.9, but it's already gone as far as current git history
goes - 2.6.12-rc2.
AFAICS there's a behaviour change with the current change.
The lseek is not completely mutually exclusive with the
vcs_read/vcs_write - the file->f_pos might get updated
via lseek callback during the vcs_read/vcs_write processing.
I tried to find out if the prefered behaviour is to keep
this in sync within read/write/lseek functions, but I did
not find any pattern on different places.
I guess if user end up calling write/lseek from different
threads she should know what she's doing. If needed we
could use dedicated fd mutex/buffer.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Using:
gcc (GCC) 4.5.0 20100610 (prerelease)
with CONFIG_CONSOLE_TRANSLATIONS=n, the following warnings are seen:
drivers/char/vt_ioctl.c: In function ‘vt_ioctl’:
drivers/char/vt_ioctl.c:1309:4: warning: statement with no effect
drivers/char/vt.c: In function ‘vc_allocate’:
drivers/char/vt.c:774:3: warning: statement with no effect
drivers/video/console/vgacon.c: In function ‘vgacon_init’:
drivers/video/console/vgacon.c:587:3: warning: statement with no effect
drivers/video/console/vgacon.c: In function ‘vgacon_deinit’:
drivers/video/console/vgacon.c:606:2: warning: statement with no effect
drivers/video/console/fbcon.c: In function ‘fbcon_init’:
drivers/video/console/fbcon.c:1087:3: warning: statement with no effect
drivers/video/console/fbcon.c:1089:3: warning: statement with no effect
drivers/video/console/fbcon.c: In function ‘fbcon_set_disp’:
drivers/video/console/fbcon.c:1369:3: warning: statement with no effect
drivers/video/console/fbcon.c:1371:3: warning: statement with no effect
This is because several functions in include/linux/vt_kern.h are
defined to (0). Convert them to static inline functions to
silence the warnings and gain a bit of type safety.
Signed-off-by: Kevin Winchester <kjwinchester@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Jesse's initial patch commit said:
"At panic time (i.e. when oops_in_progress is set) we should try a bit
harder to update the screen and make sure output gets to the VT, since
some drivers are capable of flipping back to it.
So make sure we try to unblank and update the display if called from a
panic context."
I've enhanced this to add a flag to the vc that console layer can set to
indicate they want this behaviour to occur. This also adds support to
fbcon for that flag and adds an fb flag for drivers to indicate they want
to use the support. It enables this for KMS drivers.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: James Simmons <jsimmons@infradead.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add support for setting a global default for whether or not a visible
cursor should be enabled when creating VCs. The default will be to do so,
unless overridden by the user at boot time or by a driver.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
LKML-Reference: <1258143251-5818-1-git-send-email-mjg@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
In the past someone gratuitiously borrowed chunks of kernel internal vt
code and dumped them in kernel/power. They have all sorts of deep relations
with the vt code so put them in the vt tree instead
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is needed and requested in various forms for ConsoleKit, screenblank
handling and the like so do the job with a single interface. Also build the
interface so that unlike VT_WAITACTIVE and friends it won't miss events.
FIXME: Should this be a waitactive ioctl or a new device file you can poll
and read events from. We need the code anyway to fix up the existing broken
wait for console switch logic but the ConsoleKit people would prefer the
new device to the ioctl we have here
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Carry on pushing code out of tty_io when it belongs to other drivers. I'm
not 100% happy with some of this and it will be worth revisiting some of the
exports later when the restructuring work is done.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This moves it to being a tty operation. That removes special cases and now
also means that resize can be picked up by um and other non vt consoles
which may have a resize operation.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/video/console/promcon.c:158: error: implicit declaration of
function 'con_protect_unimap'
Introduced by commit a29ccf6f82
("embedded: fix vc_translate operator precedence").
Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Cc: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This fixes a bug in operator precedence in the newly introduced vc_translate
macro. Without this fix, the translation of some characters on the
kernel console is garbled.
This patch was copied to the e-mail list previously for testing. Now,
all reports confirm that it works, so this is an official post for
application.
Signed-off-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
By turning off the new CONSOLE_TRANSLATIONS option and dropping the
associated code and tables from the kernel, we can save about 7KiB.
Taken from linux-tiny project by Tim Bird and mangled further by dwmw2.
Signed-off-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Add a proper prototype for vty_init() in include/linux/vt_kern.h
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As of now, the kernel defaults to non-unicode and XLATE for the keyboard.
We've been changing this in Fedora, but that requires patching the defaults
in the kernel.
The attached introduces CONFIG_VT_UNICODE, which sets the console in
unicode mode by default on boot, including both the virtual terminal and
the keyboard driver.
Signed-off-by: Bill Nottingham <notting@redhat.com>
Cc: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow fbcon to select the primary display adapter using the
fb_is_primary_device() arch-specific helper. If a a primary adapter is
detected, fbcon will unbind the old adapter from the VT layer, then rebind
using the new adapter. This requires that bind_/unbind_con_driver() be made
public.
Because this feature may produce unexpected behavior (from the user's POV),
this must be explicitly enabled in Kconfig.
[akpm@linux-foundation.org: export unbind_con_driver]
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The virtual console driver uses a semaphore as mutex. Use the mutex API
instead of the (binary) semaphore.
Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When the console is in VT_AUTO+KD_GRAPHICS mode, switching to the
SUSPEND_CONSOLE fails, resulting in vt_waitactive() waiting indefinitely or
until the task is interrupted. This patch tests if a console switch can
occur in set_console() and returns early if a console switch is not
possible.
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Andrew Johnson <ajohnson@intrinsyc.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is such a rare path it took me a while to figure out how to test
this after soring out the locking.
This patch does several things.
- The variables used are moved into a structure and declared in vt_kern.h
- A spinlock is added so we don't have SMP races updating the values.
- Instead of raw pid_t value a struct_pid is used to guard against
pid wrap around issues, if the daemon to spawn a new console dies.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The current kernel serializes console resizes but does not serialize the
resize against the tty structure updates. This means that while two
parallel resizes cannot mess up the console you can get incorrect results
reported.
Secondly while doing this I added vc_lock_resize() to lock and resize the
console. This leaves all knowledge of the console_sem in the vt/console
driver and kicks it out of the tty layer, which is good
Thirdly while doing this I decided I couldn't stand "disallocate" any
longer so I switched it to "deallocate".
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
MAX_NR_CONSOLES, fg_console, want_console and last_console are more of a
function of the VT layer than the TTY one. Moving these to vt.h and vt_kern.h
allows all of the framebuffer and VT console drivers to remove their
dependency on tty.h.
[akpm@osdl.org: fix alpha build]
Signed-off-by: Jon Smirl <jonsmir@gmail.com>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* git://git.infradead.org/hdrcleanup-2.6: (63 commits)
[S390] __FD_foo definitions.
Switch to __s32 types in joystick.h instead of C99 types for consistency.
Add <sys/types.h> to headers included for userspace in <linux/input.h>
Move inclusion of <linux/compat.h> out of user scope in asm-x86_64/mtrr.h
Remove struct fddi_statistics from user view in <linux/if_fddi.h>
Move user-visible parts of drivers/s390/crypto/z90crypt.h to include/asm-s390
Revert include/media changes: Mauro says those ioctls are only used in-kernel(!)
Include <linux/types.h> and use __uXX types in <linux/cramfs_fs.h>
Use __uXX types in <linux/i2o_dev.h>, include <linux/ioctl.h> too
Remove private struct dx_hash_info from public view in <linux/ext3_fs.h>
Include <linux/types.h> and use __uXX types in <linux/affs_hardblocks.h>
Use __uXX types in <linux/divert.h> for struct divert_blk et al.
Use __u32 for elf_addr_t in <asm-powerpc/elf.h>, not u32. It's user-visible.
Remove PPP_FCS from user view in <linux/ppp_defs.h>, remove __P mess entirely
Use __uXX types in user-visible structures in <linux/nbd.h>
Don't use 'u32' in user-visible struct ip_conntrack_old_tuple.
Use __uXX types for S390 DASD volume label definitions which are user-visible
S390 BIODASDREADCMB ioctl should use __u64 not u64 type.
Remove unneeded inclusion of <linux/time.h> from <linux/ufs_fs.h>
Fix private integer types used in V4L2 ioctls.
...
Manually resolve conflict in include/linux/mtd/physmap.h
From: Andrew Morton <akpm@osdl.org>
Revert commit ff4da2e262.
It broke APM suspend, probably because APM doesn't switch back to a VT
when suspending.
Tracked down by Matt Mackall <mpm@selenic.com>
Rafael sayeth:
"It only fixed the theoretical issue that a quick-handed user could
switch to X after processes have been frozen and before the devices
are suspended.
With the current userland suspend tools it shouldn't be necessary."
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It is unsafe to suspend devices if the hardware is controlled by X. Add an
extra check to prevent this from happening.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Greg Kroah-Hartman