Commit 699390354d
('pty: Ignore slave pty close() if never successfully opened')
introduced a bug with ptys whereby a write() in parallel with an
open() on an existing pty could mistakenly indicate an I/O error.
Only indicate an I/O error if the condition on open() actually exists.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Mikael Pettersson <mikpe@it.uu.se>
Cc: stable <stable@vger.kernel.org> # 3.9
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
Adds support for "High Speed Serial Communications Interface with FIFO",
essentially a SCIF with 128-byte FIFOs and more accurate baud rate
generator.
Signed-off-by: Ulrich Hecht <ulrich.hecht@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
This augments the PL011 UART driver to utilize the new pinctrl
core PM helpers to transition the driver to default and sleep
states, cutting away some boilerplate code.
Cc: Hebbar Gururaja <gururaja.hebbar@ti.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
minimal support for am43x SoCs.
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Merge tag 'omap-for-v3.11/soc-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/soc
From Tony Lindgren:
Omap SoC changes. Mostly improves am33xx support, and adds
minimal support for am43x SoCs.
* tag 'omap-for-v3.11/soc-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: OMAP2+: AM43x: SRAM base and size
ARM: OMAP2+: AM43x: GP or HS ?
ARM: OMAP2+: AM43x: early init
ARM: OMAP2+: AM43x: static mapping
ARM: OMAP2+: AM437x: SoC revision detection
ARM: OMAP2+: AM43x: soc_is support
ARM: OMAP2+: AM43x: kbuild
ARM: OMAP2+: AM43x: Kconfig
ARM: OMAP2+: separate out OMAP4 restart
ARM: AM33XX: clk: Add clock node for EHRPWM TBCLK
ARM: OMAP3: clock data: get rid of unused USB host clock aliases and dummies
ARM: OMAP2+: AM33xx: Add missing reset status info to GFX hwmod
+ Linux 3.10-rc5
Signed-off-by: Olof Johansson <olof@lixom.net>
The console's clocks are disabled after the uart driver is probed.
It makes that we can see less log from the console now
(though we still can get all the log by the `dmesg`).
So enable the clocks for console, and we can see all the log again.
This patch also disables the sport->clk_per when we fail to enable
the sport->clk_ipg;
Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add Freescale lpuart driver support. The lpuart device
can be found on Vybrid VF610 and Layerscape LS-1 SoCs.
Signed-off-by: Jingchang Lu <b35083@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some improvements in the Kconfig text:
- Vendor is Freescale now
- Provide a better example for the console parameter, which is something like
console=ttymxc0
- Do not pass the names of ancient bootloaders
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need to only allow the serial driver to be built-in.
Allow the imx serial driver to be built as a module.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When CONFIG_SERIAL_IMX_CONSOLE is not selected the following build warnings
appear:
drivers/tty/serial/imx.c:274:13: warning: 'imx_port_ucrs_save' defined but not used [-Wunused-function]
drivers/tty/serial/imx.c:283:13: warning: 'imx_port_ucrs_restore' defined but not used [-Wunused-function]
imx_port_ucrs_save() and imx_port_ucrs_restore() are only used when
CONFIG_CONSOLE_POLL or CONFIG_SERIAL_IMX_CONSOLE are selected, so protect these
functions declaration with a proper ifdef.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If pinctrl_get_select_default() fails, sirfsoc_uart_probe()
returns IS_ERR(result) instead of PTR_ERR(result).
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The dereference to 'up' should be moved below the NULL test.
Introduced by commit ddd85e225c
(serial: omap: prevent runtime PM for "no_console_suspend")
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Current code opens the clocks when the uart driver is probed.
This will wastes some power if several uarts are enabled, but not really
used.
So close these clocks for uart, and enable the clocks only when
the uart is used.
Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Attempt to reboot the system gracefully when a key combo is detected.
If the reste combination is pressed the 2nd time we assume that graceful
reboot failed and perform emergency reboot. This fucntionality is useful
when UI is stuck but the system is otherwise working fine.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Support for the Stallion multiport serial drivers was removed in v3.1.
Clean up their last references in the tree: mainly an outdated Kconfig
entry and unneeded documentation.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The uart works in the DCE mode by default, but sometime we need it
works at the DTE mode.
This patch adds the support for the DTE mode.
Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A recent bug fix in 3.10, ddd85e225c "serial: omap: prevent runtime PM for
"no_console_suspend"", introduced a regression from an obvious typo:
drivers/tty/serial/omap-serial.c:1677:14: error: 'serial_omap_complete'
undeclared here (not in a function)
This changes the incorrectly added macro to the one that we need instead.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Bin Liu <b-liu@ti.com>
Acked-by: Sourav Poddar<sourav.poddar@ti.com>
Tested-by: Sourav Poddar<sourav.poddar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "runtime idle" helper routine, rpm_idle(), currently ignores
return values from .runtime_idle() callbacks executed by it.
However, it turns out that many subsystems use
pm_generic_runtime_idle() which checks the return value of the
driver's callback and executes pm_runtime_suspend() for the device
unless that value is not 0. If that logic is moved to rpm_idle()
instead, pm_generic_runtime_idle() can be dropped and its users
will not need any .runtime_idle() callbacks any more.
Moreover, the PCI, SCSI, and SATA subsystems' .runtime_idle()
routines, pci_pm_runtime_idle(), scsi_runtime_idle(), and
ata_port_runtime_idle(), respectively, as well as a few drivers'
ones may be simplified if rpm_idle() calls rpm_suspend() after 0 has
been returned by the .runtime_idle() callback executed by it.
To reduce overall code bloat, make the changes described above.
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
when platform_driver_register broken, we should unregister ucc_uart_driver
Signed-off-by: Libo chen <libo.chen@huawei.com>
Acked-by: Timur Tabi <timur@tabi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add the missing uart_unregister_driver() before return from
s3c24xx_serial_modinit() in the error handling case.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The usage of strict_strtoul() is not preferred, because
strict_strtoul() is obsolete. Thus, kstrtoul() should be
used.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MPC5125 PSC controller has different register layout than MPC5121.
To support MPC5125 PSC in this driver we have to provide further
psc_ops functions for SoC specific register accesses.
Add new register access functions to the psc_ops structure and
provide MPC52xx and MPC512x specific implementation for them.
Then replace remaining direct register accesses in the driver by
appropriate psc_ops function calls. The subsequent patch can now
add MPC5125 specific set of psc_ops functions.
Signed-off-by: Vladimir Ermakov <vooon341@gmail.com>
Signed-off-by: Matteo Facchinetti <matteo.facchinetti@sirius-es.it>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the wrapper functions for getting and setting the driver data using
platform_device instead of using dev_{get,set}_drvdata() with &pdev->dev,
so we can directly pass a struct platform_device.
Also, unnecessary dev_set_drvdata() is removed, because the driver core
clears the driver data to NULL after device_release or on probe failure.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'wmt_dt_ids' is always compiled in. Hence of_match_ptr is not
necessary.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit cfcec52e97.
This regresses a longstanding behaviour on X86 systems, which end up with
PCI serial ports moving between ttyS4 and ttyS0 when you bisect to opposite
sides of this commit, resulting in the need to constantly modify the console
setting in order to bisect across it.
Please revert, we can work on solving this for ARM platforms in a less
disruptive way.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: Karthik Manamcheri <karthik.manamcheri@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ensure that the uart controller clock is enabled prior to writing to the
interrupt mask and pending registers in the s3c24xx_serial_init_port
function.
Signed-off-by: Chander Kashyap <chander.kashyap@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We only want to enable hardware flow control if RTS/CTS pins
are connected.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Migrate the Zynq platform and its drivers to use the new clock
controller driver.
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
We didn't have any fixes sent up for -rc2, so this is a slightly larger
batch. A bit all over the place platform-wise; OMAP, at91, marvell,
renesas, sunxi, ux500, etc.
I tried to summarize highlights but there isn't a whole lot to point
out. Lots of little things fixed all over. A couple of defconfig updates
due to new/changing options.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"We didn't have any fixes sent up for -rc2, so this is a slightly
larger batch. A bit all over the place platform-wise; OMAP, at91,
marvell, renesas, sunxi, ux500, etc.
I tried to summarize highlights but there isn't a whole lot to point
out. Lots of little things fixed all over. A couple of defconfig
updates due to new/changing options."
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (44 commits)
ARM: at91/sama5: fix incorrect PMC pcr div definition
ARM: at91/dt: fix macb pinctrl_macb_rmii_mii_alt definition
ARM: at91: at91sam9n12: move external irq declatation to DT
ARM: shmobile: marzen: Use error values in usb_power_*
ARM: tegra: defconfig fixes
ARM: nomadik: fix IRQ assignment for SMC ethernet
ARM: vt8500: Add missing NULL terminator in dt_compat
clk: tegra: add ac97 controller clock
clk: tegra: remove USB from clk init table
ARM: dts: mvebu: Fix wrong the address reg value for the L2-cache node
ARM: plat-orion: Fix num_resources and id for ge10 and ge11
ARM: OMAP2+: hwmod: Remove sysc slave idle and auto idle apis
SERIAL: OMAP: Remove the slave idle handling from the driver
ARM: OMAP2+: serial: Remove the un-used slave idle hooks
ARM: OMAP2+: hwmod-data: UART IP needs software control to manage sidle modes
ARM: OMAP2+: hwmod: Add a new flag to handle SIDLE in SWSUP only in active
ARM: OMAP2+: hwmod: Fix sidle programming in _enable_sysc()/_idle_sysc()
arm: mvebu: fix the 'ranges' property to handle PCIe
ARM: mvebu: select ARCH_REQUIRE_GPIOLIB for mvebu platform
ARM: AM33XX: Add missing .clkdm_name to clkdiv32k_ick clock
...
mxser_port->opmode_ioaddr is initialized only for MOXA_MUST_MU860_HWID
chips, but no precautions have been undertaken to prevent reading and
writing to undefined port number.
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is the same controller as on Intel Lynxpoint but the
ACPI ID is different.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
The semantics of a rw semaphore are almost ideally suited
for tty line discipline lifetime management; multiple active
threads obtain "references" (read locks) while performing i/o
to prevent the loss or change of the current line discipline
(write lock).
Unfortunately, the existing rw_semaphore is ill-suited in other
ways;
1) TIOCSETD ioctl (change line discipline) expects to return an
error if the line discipline cannot be exclusively locked within
5 secs. Lock wait timeouts are not supported by rwsem.
2) A tty hangup is expected to halt and scrap pending i/o, so
exclusive locking must be prioritized.
Writer priority is not supported by rwsem.
Add ld_semaphore which implements these requirements in a
semantically similar way to rw_semaphore.
Writer priority is handled by separate wait lists for readers and
writers. Pending write waits are priortized before existing read
waits and prevent further read locks.
Wait timeouts are trivially added, but obviously change the lock
semantics as lock attempts can fail (but only due to timeout).
This implementation incorporates the write-lock stealing work of
Michel Lespinasse <walken@google.com>.
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
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>
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>
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>
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>
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>
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>
I meet emacs hang in start if I do the operation below:
1: echo 3 > /proc/sys/vm/drop_caches
2: emacs BigFile
3: Press CTRL-S follow 2 immediately
Then emacs hang on, CTRL-Q can't resume, the terminal
hang on, you can do nothing with this terminal except
close it.
The reason is before emacs takeover control the tty,
we use CTRL-S to XOFF it. Then when emacs takeover the
control, it may don't use the flow-control, so emacs hang.
This patch fix it.
This patch will fix a kind of strange tty relation hang problem,
I believe I meet it with vim in ssh, and also see below bug report:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=465823
Signed-off-by: Wang YanQing <udknight@gmail.com>
Cc: stable <stable@vger.kernel.org>
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>
We have registered platform driver when module init, and
need unregister it when module exit.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>