The only possible problem of using mutex_lock() instead of trylock
is about deadlock.
If there aren't any locks held before calling blkdev_reread_part(),
deadlock can't be caused by this conversion.
If there are locks held before calling blkdev_reread_part(),
and if these locks arn't required in open, close handler and I/O
path, deadlock shouldn't be caused too.
Both user space's ioctl(BLKRRPART) and md_setup_drive() from
init/do_mounts_md.c belongs to the 1st case, so the conversion is safe
for the two cases.
For loop, the previous patches in this pathset has fixed the ABBA lock
dependency, so the conversion is OK.
For nbd, tx_lock is held when calling the function:
- both open and release won't hold the lock
- when blkdev_reread_part() is run, I/O thread has been stopped
already, so tx_lock won't be acquired in I/O path at that time.
- so the conversion won't cause deadlock for nbd
For dasd, both dasd_open(), dasd_release() and request function don't
acquire any mutex/semphone, so the conversion should be safe.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch exports blkdev_reread_part() for block drivers, also
introduce __blkdev_reread_part().
For some drivers, such as loop, reread of partitions can be run
from the release path, and bd_mutex may already be held prior to
calling ioctl_by_bdev(bdev, BLKRRPART, 0), so introduce
__blkdev_reread_part for use in such cases.
CC: Christoph Hellwig <hch@lst.de>
CC: Jens Axboe <axboe@kernel.dk>
CC: Tejun Heo <tj@kernel.org>
CC: Alexander Viro <viro@zeniv.linux.org.uk>
CC: Markus Pargmann <mpa@pengutronix.de>
CC: Stefan Weinhuber <wein@de.ibm.com>
CC: Stefan Haberland <stefan.haberland@de.ibm.com>
CC: Sebastian Ott <sebott@linux.vnet.ibm.com>
CC: Fabian Frederick <fabf@skynet.be>
CC: Ming Lei <ming.lei@canonical.com>
CC: David Herrmann <dh.herrmann@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Peter Zijlstra <peterz@infradead.org>
CC: nbd-general@lists.sourceforge.net
CC: linux-s390@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This driver adds support for the PCIe 2.0 controller found on the BCMA bus.
This controller can be found on (mostly) all Broadcom BCM470X / BCM5301X
ARM SoCs.
The driver found in the Broadcom SDK does some more stuff, like setting up
some DMA memory areas, chaining MPS and MRRS to 512 and also some PHY
changes like "improving" the PCIe jitter and doing some special
initialization for the 3rd PCIe port.
This was tested on a bcm4708 board with 2 PCIe ports and wireless cards
connected to them.
PCI_DOMAINS is needed by this driver, because normally there is more than
one PCIe controller and without PCI_DOMAINS only the first controller gets
registered. This controller gets 6 IRQs; the last one is trigged by all
IRQ events.
[bhelgaas: fix "GPLv2" MODULE_LICENSE typo]
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Ray Jui <rjui@broadcom.com.com>
Makefile.boot is not used anymore, remove it.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
include/soc/at91/at91rm9200_sdramc.h is replaced by
include/linux/mfd/syscon/atmel-smc.h as this is actually a syscon device.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Use the defines from atmel-mc.h instead of at91rm9200_sdramc.h
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Use syscon/regmap to configure the smc part of the memory controller. This
allows to avoid using mach/at91rm9200_mc.h and mach/at91_ramc.h and to compile
the driver in a multiplatform configuration.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
The at91rm9200 memory controller is not simply an SDRAM controller. It also
controls the EBI (External Bus Interface), the SMC (Static Memory Controller)and
the Burst Flash Controller.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
The at91rm9200 SoC embeds a Memory Controller block which is used to
configure several aspects of the platform:
- AHB/APB Bus behavior
- SDRAM Controller
- EBI (External Bus Interface) and SMC (Static Memory Controller) config
Those registers might be accessed by different drivers, hence we need to
define it as a syscon device.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
sam9_smc.c has no users anymore, remove it along with both sam9_smc.h and
mach/at91sam9_smc.h
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Use syscon/regmap to configure the smc. This allows to avoid using
at91sam9_smc.h and to compile the driver in a multiplatform configuration.
The driver will still not probe until the proper DT bindings are added. That
binding will include an atmel,smc property that is a phandle to the SMC the CF
controller is connected to.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Dan Carpenter pointed out an inconsistent null pointer check
in smb2_hdr_assemble that was pointed out by static checker.
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Sachin Prabhu <sprabhu@redhat.com>
CC: Dan Carpenter <dan.carpenter@oracle.com>w
The iProc core PCIe driver defaults to using of_irq_parse_and_map_pci() for
IRQ mapping. Add iproc_pcie.map_irq so bus interfaces that don't use
device tree can override this by supplying their own IRQ mapping function.
[bhelgaas: changelog]
Posting: http://lkml.kernel.org/r/1431465781-10753-1-git-send-email-hauke@hauke-m.de
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ray Jui <rjui@broadcom.com.com>
Recent fix for BCM4704 reboots has to be extended as the same problem
affects Linksys WRT350N v1 (BCM4705).
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Reported-by: Daniel Gimpelevich <daniel@gimpelevich.san-francisco.ca.us>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
When a station does a channel switch, it's not well defined what its TDLS
peers would do. Avoid a situation when the local side marks a potentially
disconnected peer as a TDLS peer.
Keeping peers connected through CSA is doubly problematic with the upcoming
TDLS WIDER-BW feature which allows peers to widen the BSS channel. The
new channel transitioned-to might not be compatible and would require
a re-negotiation anyway.
Make sure to disallow new TDLS link during CSA.
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Some splats I was seeing:
(a) WARNING: CPU: 1 PID: 0 at /devel/src/linux/net/mac80211/wep.c:102 ieee80211_wep_add_iv
(b) WARNING: CPU: 1 PID: 0 at /devel/src/linux/net/mac80211/wpa.c:73 ieee80211_tx_h_michael_mic_add
(c) WARNING: CPU: 3 PID: 0 at /devel/src/linux/net/mac80211/wpa.c:433 ieee80211_crypto_ccmp_encrypt
I've seen (a) and (b) with ath9k hw crypto and (c)
with ath9k sw crypto. All of them were related to
insufficient skb tailroom and I was able to
trigger these with ping6 program.
AP_VLANs may inherit crypto keys from parent AP.
This wasn't considered and yielded problems in
some setups resulting in inability to transmit
data because mac80211 wouldn't resize skbs when
necessary and subsequently drop some packets due
to insufficient tailroom.
For efficiency purposes don't inspect both AP_VLAN
and AP sdata looking for tailroom counter. Instead
update AP_VLAN tailroom counters whenever their
master AP tailroom counter changes.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Due to remain-on-channel scheduling delays, when we split an ROC
while coalescing, we'll usually get a picture like this:
existing ROC: |------------------|
current time: ^
new ROC: |------| |-------|
If the expected response frames are then transmitted by the peer
in the hole between the two fragments of the new ROC, we miss
them and the process (e.g. ANQP query) fails.
mac80211 expects that the window to miss something is small:
existing ROC: |------------------|
new ROC: |------||-------|
but that's normally not the case.
To avoid this problem, coalesce only if the new ROC's duration
is <= the remaining time on the existing one:
existing ROC: |------------------|
new ROC: |-----|
and never split a new one but schedule it afterwards instead:
existing ROC: |------------------|
new ROC: |-------------|
type=bugfix
bug=not-tracked
fixes=unknown
Reported-by: Matti Gottlieb <matti.gottlieb@intel.com>
Reviewed-by: EliadX Peller <eliad@wizery.com>
Reviewed-by: Matti Gottlieb <matti.gottlieb@intel.com>
Tested-by: Matti Gottlieb <matti.gottlieb@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Drivers with fast-xmit (e.g. ath10k) running in
AP_VLAN setups would fail to communicate with
connected 4addr stations.
The reason was when new station associates it
first goes into master AP interface. It is not
until later that a dedicated AP_VLAN is created
for it and the station itself is moved there.
After that Tx directed at the station should use
4addr header. However fast-xmit wasn't
recalculated and 3addr header remained to be used.
This in turn caused the connected 4addr stations
to drop packets coming from the AP until some
other event would cause fast-xmit to recalculate
for that station (which could never come).
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The kernel-doc description for the drv_priv member of
struct ieee80211_txq was missing, leading to errors.
Add a suitable description to fix that.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Use dev_pm_ops instead of the legacy suspend/resume callbacks for the wiphy
class suspend and resume operations.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Use dev_pm_ops instead of the legacy suspend/resume callbacks for the
rfkill class suspend and resume operations.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
These state vars are used for more than just ber calculation, also
fix typo.
Signed-off-by: Jemma Denson <jdenson@gmail.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
BER & UCB aren't available unless we're locked; don't update dvbv5
stats when not locked and mark these counters as unavailable.
Signed-off-by: Jemma Denson <jdenson@gmail.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
DVBv3 is a legacy API. Drivers should use DVBv5, in order to support
modern applications. So, implement UCB using dvbv5.
Signed-off-by: Jemma Denson <jdenson@gmail.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Instead of reading BER again for DVBv3 call, use the value from the cache.
Signed-off-by: Jemma Denson <jdenson@gmail.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
DVBv3 is a legacy API. Drivers should use DVBv5, in order to support
modern applications. So, implement BER using dvbv5.
Signed-off-by: Jemma Denson <jdenson@gmail.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Use const on the static data, as gcc may optimize better the
code. Also, would prevent that some code would override the
data there.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>
As reported by smatch:
drivers/media/dvb-frontends/cx24120.c: In function 'cx24120_message_send':
drivers/media/dvb-frontends/cx24120.c:368:6: warning: variable 'ret' set but not used [-Wunused-but-set-variable]
int ret, ficus;
^
The values written by cx24120 are never checked. So, remove the
check here too. That's said, the best would be to do the reverse,
but globally: to properly handle the error codes.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>
This reverts commit c055d5b03b.
There are two issues:
'dnat_took_place' made me think that this is related to
-j DNAT/MASQUERADE.
But thats only one part of the story. This is also relevant for SNAT
when we undo snat translation in reverse/reply direction.
Furthermore, I originally wanted to do this mainly to avoid
storing ipv6 addresses once we make DNAT/REDIRECT work
for ipv6 on bridges.
However, I forgot about SNPT/DNPT which is stateless.
So we can't escape storing address for ipv6 anyway. Might as
well do it for ipv4 too.
Reported-and-tested-by: Bernhard Thaler <bernhard.thaler@wvnet.at>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
After improving setsockopt() coverage in trinity, I started triggering
vmalloc failures pretty reliably from this code path:
warn_alloc_failed+0xe9/0x140
__vmalloc_node_range+0x1be/0x270
vzalloc+0x4b/0x50
__do_replace+0x52/0x260 [ip_tables]
do_ipt_set_ctl+0x15d/0x1d0 [ip_tables]
nf_setsockopt+0x65/0x90
ip_setsockopt+0x61/0xa0
raw_setsockopt+0x16/0x60
sock_common_setsockopt+0x14/0x20
SyS_setsockopt+0x71/0xd0
It turns out we don't validate that the num_counters field in the
struct we pass in from userspace is initialized.
The same problem also exists in ebtables, arptables, ipv6, and the
compat variants.
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nfnetlink_{log,queue}_init() register the netlink callback nf*_rcv_nl_event
before registering the pernet_subsys, but the callback relies on data
structures allocated by pernet init functions.
When nfnetlink_{log,queue} is loaded, if a netlink message is received after
the netlink callback is registered but before the pernet_subsys is registered,
the kernel will panic in the sequence
nfulnl_rcv_nl_event
nfnl_log_pernet
net_generic
BUG_ON(id == 0) where id is nfnl_log_net_id.
The panic can be easily reproduced in 4.0.3 by:
while true ;do modprobe nfnetlink_log ; rmmod nfnetlink_log ; done &
while true ;do ip netns add dummy ; ip netns del dummy ; done &
This patch moves register_pernet_subsys to earlier in nfnetlink_log_init.
Notice that the BUG_ON hit in 4.0.3 was recently removed in 2591ffd308
["netns: remove BUG_ONs from net_generic()"].
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
User visible:
- Fix "Command" sort_entry's cmp and collapse function (Jiri Olsa)
- Load map's symtab before 'perf probe' glob matching (Wang Nan)
- Set vmlinux_path__nr_entries to 0 in vmlinux_path__exit, to fix
the use case where this code is called multiple times, which wasn't
that common when it was introduced but seems to be now (Wang Nan).
Infrastructure:
- Protect dso symtab and cache operations with a mutex (Namhyung Kim)
- Make all refcnt operations use atomic.h (Arnaldo Carvalho de Melo)
- Install libtraceevent.a into libdir (Wang Nan)
Build fixes:
- Fix one build failure on RHEL5 by making 'perf bench numa' use the
__weak sched_getcpu() provided by cloexec.h (Arnaldo Carvalho de Melo)
- Fix dwarf-aux.c compilation on i386 (Jiri Olsa)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Fix "Command" sort_entry's cmp and collapse function (Jiri Olsa)
- Load map's symtab before 'perf probe' glob matching (Wang Nan)
- Set vmlinux_path__nr_entries to 0 in vmlinux_path__exit, to fix
the use case where this code is called multiple times, which wasn't
that common when it was introduced but seems to be now (Wang Nan).
Infrastructure changes:
- Protect dso symtab and cache operations with a mutex (Namhyung Kim)
- Make all refcnt operations use atomic.h (Arnaldo Carvalho de Melo)
- Install libtraceevent.a into libdir (Wang Nan)
Build fixes:
- Fix one build failure on RHEL5 by making 'perf bench numa' use the
__weak sched_getcpu() provided by cloexec.h (Arnaldo Carvalho de Melo)
- Fix dwarf-aux.c compilation on i386 (Jiri Olsa)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The MPX feature requires eager KVM FPU restore support. We have verified
that MPX cannot work correctly with the current lazy KVM FPU restore
mechanism. Eager KVM FPU restore should be enabled if the MPX feature is
exposed to VM.
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Signed-off-by: Liang Li <liang.z.li@intel.com>
[Also activate the FPU on AMD processors. - Paolo]
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The dapm field of the snd_soc_codec struct is eventually going to be
removed, in preparation for this replace all manual access to
codec->dapm.bias_level with snd_soc_codec_get_bias_level() and replace all
other manual access to codec->dapm with snd_soc_codec_get_dapm().
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dapm field of the snd_soc_codec struct is eventually going to be
removed, in preparation for this replace all manual access to
codec->dapm.bias_level with snd_soc_codec_get_bias_level() and replace all
other manual access to codec->dapm with snd_soc_codec_get_dapm().
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dapm field of the snd_soc_codec struct is eventually going to be
removed, in preparation for this replace all manual access to
codec->dapm.bias_level with snd_soc_codec_get_bias_level().
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dapm field of the snd_soc_codec struct is eventually going to be
removed, in preparation for this replace all manual access to
codec->dapm.bias_level with snd_soc_codec_get_bias_level() and replace all
other manual access to codec->dapm with snd_soc_codec_get_dapm().
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dapm field of the snd_soc_codec struct is eventually going to be
removed, in preparation for this replace all manual access to
codec->dapm.bias_level with snd_soc_codec_get_bias_level() and
snd_soc_codec_init_bias_level().
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dapm field of the snd_soc_codec struct is eventually going to be
removed, in preparation for this replace all manual access to
codec->dapm.bias_level with snd_soc_codec_get_bias_level() and replace all
other manual access to codec->dapm with snd_soc_codec_get_dapm().
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
The dapm field of the snd_soc_codec struct is eventually going to be
removed, in preparation for this replace all manual access to
codec->dapm with snd_soc_codec_get_dapm().
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Conflicts:
arch/x86/kernel/i387.c
This commit is conflicting:
e88221c50c ("x86/fpu: Disable XSAVES* support for now")
These functions changed a lot, move the quirk to arch/x86/kernel/fpu/init.c's
fpu__init_system_xstate_size_legacy().
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We assumed all touch interfaces report touch data. But, Bamboo
and Intuos non-touch devices report express keys on touch
interface. We need to check touch_max before counting touches.
Reported-by: Tasos Sahanidis <tasos@tasossah.com>
Signed-off-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The kernel's handling of 'compacted' xsave state layout is buggy:
http://marc.info/?l=linux-kernel&m=142967852317199
I don't have such a system, and the description there is vague, but
from extrapolation I guess that there were two kinds of bugs
observed:
- boot crashes, due to size calculations being wrong and the dynamic
allocation allocating a too small xstate area. (This is now fixed
in the new FPU code - but still present in stable kernels.)
- FPU state corruption and ABI breakage: if signal handlers try to
change the FPU state in standard format, which then the kernel
tries to restore in the compacted format.
These breakages are scary, but they only occur on a small number of
systems that have XSAVES* CPU support. Yet we have had XSAVES support
in the upstream kernel for a large number of stable kernel releases,
and the fixes are involved and unproven.
So do the safe resolution first: disable XSAVES* support and only
use the standard xstate format. This makes the code work and is
easy to backport.
On top of this we can work on enabling (and testing!) proper
compacted format support, without backporting pressure, on top of the
new, cleaned up FPU code.
Cc: <stable@vger.kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
