Brownstone does not have temperature reading circuit hooked up.
This leads to spurious interrupts.
Allow the platform layer to indicate no temperature circuit
and do not activate interrupts if no temperature control is set
Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Commit 944e192db53c "freezer: rename thaw_process() to __thaw_task()
and simplify the implementation" did not create a !CONFIG_FREEZER version
of __thaw_task().
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Some clocks can select its parent clock by CPG register.
But it might have been modified by boot-loader or something.
This patch removed fixed initial parent clock,
and setup it from their current register settings.
It works on div6 reparent clocks for now.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* git://github.com/rustyrussell/linux:
virtio-pci: make reset operation safer
virtio-mmio: Correct the name of the guest features selector
virtio: add HAS_IOMEM dependency to MMIO platform bus driver
virtio pci device reset actually just does an I/O
write, which in PCI is really posted, that is it
can complete on CPU before the device has received it.
Further, interrupts might have been pending on
another CPU, so device callback might get invoked after reset.
This conflicts with how drivers use reset, which is typically:
reset
unregister
a callback running after reset completed can race with
unregister, potentially leading to use after free bugs.
Fix by flushing out the write, and flushing pending interrupts.
This assumes that device is never reset from
its vq/config callbacks, or in parallel with being
added/removed, document this assumption.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci:
PCI hotplug: shpchp: don't blindly claim non-AMD 0x7450 device IDs
PCI: pciehp: wait 100 ms after Link Training check
PCI: pciehp: wait 1000 ms before Link Training check
PCI: pciehp: Retrieve link speed after link is trained
PCI: Let PCI_PRI depend on PCI
PCI: Fix compile errors with PCI_ATS and !PCI_IOV
PCI / ACPI: Make acpiphp ignore root bridges using PCIe native hotplug
* tag 'v3.2-rc2': (3068 commits)
Linux 3.2-rc2
hfs: add sanity check for file name length
fsl-rio: fix compile error
blackfin: Fixup export.h includes
Blackfin: add serial TX IRQ in individual platform resource
virtio-pci: fix use after free
ACPI / cpuidle: Remove acpi_idle_suspend (to fix suspend regression)
drm/radeon/kms/combios: fix dynamic allocation of PM clock modes
[CPUFREQ] db8500: fix build error due to undeclared i variable
bma023: Add SFI translation for this device
vrtc: change its year offset from 1960 to 1972
ce4100: fix a build error
arm/imx: fix imx6q mmc error when mounting rootfs
arm/imx: fix AUTO_ZRELADDR selection
arm/imx: fix the references to ARCH_MX3
ARM: mx51/53: set pwm clock parent to ipg_perclk
btrfs: rename the option to nospace_cache
drm/radeon/kms/pm: switch to dynamically allocating clock mode array
drm/radeon/kms: optimize r600_pm_profile_init
drm/radeon/kms/pm: add a proper pm profile init function for fusion
...
Conflicts:
drivers/media/radio/Kconfig
The lock_system_sleep() function is used in the memory hotplug code at
several places in order to implement mutual exclusion with hibernation.
However, this function tries to acquire the 'pm_mutex' lock using
mutex_lock() and hence blocks in TASK_UNINTERRUPTIBLE state if it doesn't
get the lock. This would lead to task freezing failures and hence
hibernation failure as a consequence, even though the hibernation call path
successfully acquired the lock.
But it is to be noted that, since this task tries to acquire pm_mutex, if it
blocks due to this, we are *100% sure* that this task is not going to run
as long as hibernation sequence is in progress, since hibernation releases
'pm_mutex' only at the very end, when everything is done.
And this means, this task is going to be anyway blocked for much more longer
than what the freezer intends to achieve; which means, freezing and thawing
doesn't really make any difference to this task!
So, to fix freezing failures, we just ask the freezer to skip freezing this
task, since it is already "frozen enough".
But instead of calling freezer_do_not_count() and freezer_count() as it is,
we use only the relevant parts of those functions, because restrictions
such as 'the task should be a userspace one' etc., might not be relevant in
this scenario.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* 'pm-freezer' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc: (24 commits)
freezer: fix wait_event_freezable/__thaw_task races
freezer: kill unused set_freezable_with_signal()
dmatest: don't use set_freezable_with_signal()
usb_storage: don't use set_freezable_with_signal()
freezer: remove unused @sig_only from freeze_task()
freezer: use lock_task_sighand() in fake_signal_wake_up()
freezer: restructure __refrigerator()
freezer: fix set_freezable[_with_signal]() race
freezer: remove should_send_signal() and update frozen()
freezer: remove now unused TIF_FREEZE
freezer: make freezing() test freeze conditions in effect instead of TIF_FREEZE
cgroup_freezer: prepare for removal of TIF_FREEZE
freezer: clean up freeze_processes() failure path
freezer: kill PF_FREEZING
freezer: test freezable conditions while holding freezer_lock
freezer: make freezing indicate freeze condition in effect
freezer: use dedicated lock instead of task_lock() + memory barrier
freezer: don't distinguish nosig tasks on thaw
freezer: remove racy clear_freeze_flag() and set PF_NOFREEZE on dead tasks
freezer: rename thaw_process() to __thaw_task() and simplify the implementation
...
Device nodes in DT can associate themselves with one or more
regulators/supply by providing a list of phandles (to regulator nodes)
and corresponding supply names.
For Example:
devicenode: node@0x0 {
...
...
vmmc-supply = <®ulator1>;
vpll-supply = <®ulator2>;
};
The driver would then do a regulator_get(dev, "vmmc"); to get
regulator1 and do a regulator_get(dev, "vpll"); to get
regulator2.
of_get_regulator() extracts the regulator node for a given
device, based on the supply name.
Use it to look up the regulator for a given consumer from device tree, during
a regulator_get(). If not found fallback and lookup through
the regulator_map_list instead.
Also, since the regulator dt nodes can use the same binding to
associate with a parent regulator/supply, allow the drivers to
specify a supply_name, which can then be used to lookup dt
to find the parent phandle.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
With device tree support for regulators, its needed that the
regulator_dev->dev device has the right of_node attached.
To be able to do this add an additional parameter to the
regulator_register() api, wherein the dt-adapted driver can
then pass this additional info onto the regulator core.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
The helper routine is meant to be used by the regulator drivers
to extract the regulator_init_data structure from the data
that is passed from device tree.
'consumer_supplies' which is part of regulator_init_data is not extracted
as the regulator consumer mappings are passed through DT differently,
implemented in subsequent patches.
Similarly the regulator<-->parent/supply mapping is handled in
subsequent patches.
Also add documentation for regulator bindings to be used to pass
regulator_init_data struct information from device tree.
Some of the regulator properties which are linux and board specific,
are left out since its not clear if they can
be in someway embedded into the kernel or passed in from DT.
They will be revisited later.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Calling del_timer_sync() on an uninitialized timer leads to a
never ending loop in lock_timer_base() that spins checking for a
non-NULL timer base. Add an assertion to debugobjects to catch
usage of uninitialized objects so that we can initialize timers
in the del_timer_sync() path before it calls lock_timer_base().
[ sboyd@codeaurora.org: Clarify commit message ]
Signed-off-by: Christine Chan <cschan@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1320724108-20788-3-git-send-email-sboyd@codeaurora.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
wait_event_freezable() and friends stop the waiting if try_to_freeze()
fails. This is not right, we can race with __thaw_task() and in this
case
- wait_event_freezable() returns the wrong ERESTARTSYS
- wait_event_freezable_timeout() can return the positive
value while condition == F
Change the code to always check __retval/condition before return.
Note: with or without this patch the timeout logic looks strange,
probably we should recalc timeout if try_to_freeze() returns T.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
There's no in-kernel user of set_freezable_with_signal() left. Mixing
TIF_SIGPENDING with kernel threads can lead to nasty corner cases as
kernel threads never travel signal delivery path on their own.
e.g. the current implementation is buggy in the cancelation path of
__thaw_task(). It calls recalc_sigpending_and_wake() in an attempt to
clear TIF_SIGPENDING but the function never clears it regardless of
sigpending state. This means that signallable freezable kthreads may
continue executing with !freezing() && stuck TIF_SIGPENDING, which can
be troublesome.
This patch removes set_freezable_with_signal() along with
PF_FREEZER_NOSIG and recalc_sigpending*() calls in freezer. User
tasks get TIF_SIGPENDING, kernel tasks get woken up and the spurious
sigpending is dealt with in the usual signal delivery path.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Count of selector voltage is required for regulator_set_voltage
to work via set_voltage_sel. VDD1/2 currently have it as zero,
so regulator_set_voltage won't work for VDD1/2.
Update count (n_voltages) for VDD1/2.
Output Voltage = (step value * 12.5 mV + 562.5 mV) * gain
With above expr, number of voltages that can be selected is
step value count * gain count
constant for gain count will be called VDD1_2_NUM_VOLT_COARSE
existing constant for step value count is VDD1_2_NUM_VOLTS,
use VDD1_2_NUM_VOLT_FINE instead to make clear that step value
is not the only component in deciding selectable voltage count
Signed-off-by: Afzal Mohammed <afzal@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Create an array of fixed size for the platform to pass regulator
initalization data through.
Passing an array of pointers to init data also allows more flexible
definition of init data as well as prevents reading past the end of the
array should the platform define an incorrectly sized array.
Signed-off-by: Kyle Manna <kyle.manna@fuel7.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Move the regulator defintions to the header so that platform board file
can use them to configure specific regulators.
Signed-off-by: Kyle Manna <kyle.manna@fuel7.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Last piece of code using ANY_I2C_BUS was deleted almost 2 years ago,
so ANY_I2C_BUS can go away as well.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
struct request_queue is allocated with __GFP_ZERO so its "node" field is
zero before initialization. This causes an oops if node 0 is offline in
the page allocator because its zonelists are not initialized. From Dave
Young's dmesg:
SRAT: Node 1 PXM 2 0-d0000000
SRAT: Node 1 PXM 2 100000000-330000000
SRAT: Node 0 PXM 1 330000000-630000000
Initmem setup node 1 0000000000000000-000000000affb000
...
Built 1 zonelists in Node order, mobility grouping on.
...
BUG: unable to handle kernel paging request at 0000000000001c08
IP: [<ffffffff8111c355>] __alloc_pages_nodemask+0xb5/0x870
and __alloc_pages_nodemask+0xb5 translates to a NULL pointer on
zonelist->_zonerefs.
The fix is to initialize q->node at the time of allocation so the correct
node is passed to the slab allocator later.
Since blk_init_allocated_queue_node() is no longer needed, merge it with
blk_init_allocated_queue().
[rientjes@google.com: changelog, initializing q->node]
Cc: stable@vger.kernel.org [2.6.37+]
Reported-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Tested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Given we dont use anymore the struct net_device *dev argument, and this
interface brings litle benefit, remove netdev_{alloc|free}_page(), to
debloat include/linux/skbuff.h a bit.
(Some drivers used a mix of these interfaces and alloc_pages())
When allocating a page given to device for DMA transfer (device to
memory), it makes sense to use a cold one (__GFP_COLD)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
CC: Dimitris Michailidis <dm@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
C assignment can handle struct in6_addr copying.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds in the infrastructure code to create the network priority
cgroup. The cgroup, in addition to the standard processes file creates two
control files:
1) prioidx - This is a read-only file that exports the index of this cgroup.
This is a value that is both arbitrary and unique to a cgroup in this subsystem,
and is used to index the per-device priority map
2) priomap - This is a writeable file. On read it reports a table of 2-tuples
<name:priority> where name is the name of a network interface and priority is
indicates the priority assigned to frames egresessing on the named interface and
originating from a pid in this cgroup
This cgroup allows for skb priority to be set prior to a root qdisc getting
selected. This is benenficial for DCB enabled systems, in that it allows for any
application to use dcb configured priorities so without application modification
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
CC: Robert Love <robert.w.love@intel.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
SKB_TRUESIZE() provides a better approximation of expected skb truesize.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFS: Revert pnfs ugliness from the generic NFS read code path
SUNRPC: destroy freshly allocated transport in case of sockaddr init error
NFS: Fix a regression in the referral code
nfs: move nfs_file_operations declaration to bottom of file.c (try #2)
nfs: when attempting to open a directory, fall back on normal lookup (try #5)
* 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
writeback: remove vm_dirties and task->dirties
writeback: hard throttle 1000+ dd on a slow USB stick
mm: Make task in balance_dirty_pages() killable
Both at91 and avr32 defines its own platform data structure for
the macb driver and both share common structures though at91
includes a currently unused phy_irq_pin. Create a common
macb_platform_data for macb that both at91 and avr32 can use. In
future we can use this to support other architectures that use the
same IP block with the macb driver.
v2: rename eth_platform_data to macb_platform_data and allow at91_ether
to share the platform data with macb.
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Tested-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
The general kernel infrastructure for adding module alises during
module post processing expects the affected device type
identification structures in a common header
<linux/mod_devicetable.h>.
This patch simple moves struct amba_id to the common header, and
adds the appropriate include in <linux/amba/bus.h>.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
* 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
TTY: ldisc, wait for ldisc infinitely in hangup
TTY: ldisc, move wait idle to caller
TTY: ldisc, allow waiting for ldisc arbitrarily long
Revert "tty/serial: Prevent drop of DCD on suspend for Tegra UARTs"
RS485: fix inconsistencies in the meaning of some variables
pch_uart: Fix DMA resource leak issue
serial,mfd: Fix CMSPAR setup
tty/serial: Prevent drop of DCD on suspend for Tegra UARTs
pch_uart: Change company name OKI SEMICONDUCTOR to LAPIS Semiconductor
pch_uart: Support new device LAPIS Semiconductor ML7831 IOH
pch_uart: Fix hw-flow control issue
tty: hvc_dcc: Fix duplicate character inputs
jsm: Change maintainership
Currently, we clear revoked flag only when a block is reused. However,
this can tigger a false journal error. Consider a situation when a block
is used as a meta block and is deleted(revoked) in ordered mode, then the
block is allocated as a data block to a file. At this moment, user changes
the file's journal mode from ordered to journaled and truncates the file.
The block will be considered re-revoked by journal because it has revoked
flag still pending from the last transaction and an assertion triggers.
We fix the problem by keeping the revoked status more uptodate - we clear
revoked flag when switching revoke tables to reflect there is no revoked
buffers in current transaction any more.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
On configs where CONFIG_JUMP_LABEL=y, we can replace in fast path a
load/compare/conditional jump by a single jump with no dcache reference.
Jump target is modified as soon as nf_hooks[pf][hook] switches from
empty state to non empty states. jump_label state is kept outside of
nf_hooks array so has no cost on cpu caches.
This patch removes the test on CONFIG_NETFILTER_DEBUG : No need to call
nf_hook_slow() at all if nf_hooks[pf][hook] is empty, this didnt give
useful information, but slowed down things a lot.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Patrick McHardy <kaber@trash.net>
CC: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This allows users to disable features such as HT, HT40,
and to modify the MCS, AMPDU, and AMSDU settings for
drivers that support it.
The MCS, AMPDU, and AMSDU features that may be disabled are
are reported in the phy-info netlink message as a mask.
Attemping to disable features that are not supported will
take no affect, but will not return errors. This is to aid
backwards compatibility in user-space apps that may not be
clever enough to deal with parsing the the capabilities mask.
This patch only enables the infrastructure. An additional
patch will enable the feature in mac80211.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The wireless-regdb now has support for mapping a country to
one DFS region. CRDA sends this to us now so process it
so we can provide that hint to drivers. This will later be
used by code for processing DFS in a way that meets the
criteria for the DFS region the country belongs to.
Signed-off-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
After "freezer: make freezing() test freeze conditions in effect
instead of TIF_FREEZE", freezing() returns authoritative answer on
whether the current task should freeze or not and freeze_task()
doesn't need or use @sig_only. Remove it.
While at it, rewrite function comment for freeze_task() and rename
@sig_only to @user_only in try_to_freeze_tasks().
This patch doesn't cause any functional change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
A kthread doing set_freezable*() may race with on-going PM freeze and
the freezer might think all tasks are frozen while the new freezable
kthread is merrily proceeding to execute code paths which aren't
supposed to be executing during PM freeze.
Reimplement set_freezable[_with_signal]() using __set_freezable() such
that freezable PF flags are modified under freezer_lock and
try_to_freeze() is called afterwards. This eliminates race condition
against freezing.
Note: Separated out from larger patch to resolve fix order dependency
Oleg pointed out.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
should_send_signal() is only used in freezer.c. Exporting them only
increases chance of abuse. Open code the two users and remove it.
Update frozen() to return bool.
Signed-off-by: Tejun Heo <tj@kernel.org>
Using TIF_FREEZE for freezing worked when there was only single
freezing condition (the PM one); however, now there is also the
cgroup_freezer and single bit flag is getting clumsy.
thaw_processes() is already testing whether cgroup freezing in in
effect to avoid thawing tasks which were frozen by both PM and cgroup
freezers.
This is racy (nothing prevents race against cgroup freezing) and
fragile. A much simpler way is to test actual freeze conditions from
freezing() - ie. directly test whether PM or cgroup freezing is in
effect.
This patch adds variables to indicate whether and what type of
freezing conditions are in effect and reimplements freezing() such
that it directly tests whether any of the two freezing conditions is
active and the task should freeze. On fast path, freezing() is still
very cheap - it only tests system_freezing_cnt.
This makes the clumsy dancing aroung TIF_FREEZE unnecessary and
freeze/thaw operations more usual - updating state variables for the
new state and nudging target tasks so that they notice the new state
and comply. As long as the nudging happens after state update, it's
race-free.
* This allows use of freezing() in freeze_task(). Replace the open
coded tests with freezing().
* p != current test is added to warning printing conditions in
try_to_freeze_tasks() failure path. This is necessary as freezing()
is now true for the task which initiated freezing too.
-v2: Oleg pointed out that re-freezing FROZEN cgroup could increment
system_freezing_cnt. Fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Paul Menage <paul@paulmenage.org> (for the cgroup portions)
TIF_FREEZE will be removed soon and freezing() will directly test
whether any freezing condition is in effect. Make the following
changes in preparation.
* Rename cgroup_freezing_or_frozen() to cgroup_freezing() and make it
return bool.
* Make cgroup_freezing() access task_freezer() under rcu read lock
instead of task_lock(). This makes the state dereferencing racy
against task moving to another cgroup; however, it was already racy
without this change as ->state dereference wasn't synchronized.
This will be later dealt with using attach hooks.
* freezer->state is now set before trying to push tasks into the
target state.
-v2: Oleg pointed out that freeze_change_state() was setting
freeze->state incorrectly to CGROUP_FROZEN instead of
CGROUP_FREEZING. Fixed.
-v3: Matt pointed out that setting CGROUP_FROZEN used to always invoke
try_to_freeze_cgroup() regardless of the current state. Patch
updated such that the actual freeze/thaw operations are always
performed on invocation. This shouldn't make any difference
unless something is broken.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Paul Menage <paul@paulmenage.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
freeze_processes() failure path is rather messy. Freezing is canceled
for workqueues and tasks which aren't frozen yet but frozen tasks are
left alone and should be thawed by the caller and of course some
callers (xen and kexec) didn't do it.
This patch updates __thaw_task() to handle cancelation correctly and
makes freeze_processes() and freeze_kernel_threads() call
thaw_processes() on failure instead so that the system is fully thawed
on failure. Unnecessary [suspend_]thaw_processes() calls are removed
from kernel/power/hibernate.c, suspend.c and user.c.
While at it, restructure error checking if clause in suspend_prepare()
to be less weird.
-v2: Srivatsa spotted missing removal of suspend_thaw_processes() in
suspend_prepare() and error in commit message. Updated.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>