This adds a tx_maxrate attribute to the tx queue sysfs entry allowing
for max-rate limiting. Along with DCB-ETS and BQL this provides another
knob to tune queue performance. The limit units are Mbps.
By default it is disabled. To disable the rate limitation after it
has been set for a queue, it should be set to zero.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull livepatching fix from Jiri Kosina:
- fix for potential race with module loading, from Petr Mladek.
The race is very unlikely to be seen in real world and has been found
by code inspection, but should be fixed for 4.0 anyway.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
livepatch: Fix subtle race with coming and going modules
The TI CC2521 is an RF power amplifier that is designed to interface
with the CC2520. Conveniently, it directly interfaces with the CC2520
and does not require any pins to be connected to a
microcontroller/processor. Adding a CC2591 increases the CC2520's range,
which is useful for border router and other wall-powered applications.
Using the CC2591 with the CC2520 requires configuring the CC2520 GPIOs
that are connected to the CC2591 to correctly set the CC2591 into TX and
RX modes. Further, TI recommends that the CC2520_TXPOWER and
CC2520_AGCCTRL1 registers are set differently to maximize the CC2591's
performance. These settings are covered in TI Application Note AN065.
This patch adds an optional `amplified` field to the cc2520 entry in the
device tree. If present, the CC2520 will be configured to operate with a
CC2591.
The expected pin mapping is:
CC2520 GPIO0 --> CC2591 EN
CC2520 GPIO5 --> CC2591 PAEN
Signed-off-by: Brad Campbell <bradjc5@gmail.com>
Acked-by: Varka Bhadram <varkabhadram@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that nobody uses max_shift and min_shift, we can safely remove
them.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the parameters max_size and min_size which are
meant to replace max_shift and min_shift.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Keeping both size and shift is silly. We only need one.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This code is no longer used now that mach-msm has been removed.
Delete it.
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: David Brown <davidb@codeaurora.org>
Cc: Bryan Huntsman <bryanh@codeaurora.org>
Cc: Daniel Walker <dwalker@fifo99.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are currently no umc drivers implementing suspend/resume, so remove
the legacy suspend/resume support from the framework. If a umc driver ever
wants to implement suspend/resume they can use dev_pm_ops, which works out
of the box without any additional support necessary from the bus itself.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some usb PHYs need power supply from vbus to make it work, eg mxs-phy, if
there is no vbus, USB PHY will not in correct state when the controller starts
to work, for host, this requires vbus should be turned on before setting port
power(PP) of ehci, to work with this kind of USB PHY design, this patch adds
a flag CI_HDRC_TURN_VBUS_EARLY_ON, can be checked by host driver to turn on
vbus while start host.
Signed-off-by: Li Jun <jun.li@freescale.com>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Occasionally, the system can't come back up after suspend/resume
due to problems of device suspending phase. This patch make
PM_TRACE infrastructure cover device suspending phase of
suspend/resume process, and the information in RTC can tell
developers which device suspending function make system hang.
Signed-off-by: Zhonghui Fu <zhonghui.fu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
I2C supports adding adapters using either a dynamic or fixed id. The
latter is provided by aliases in the DT case. To prevent id collisions
of those two types, install this function which gives us the highest
fixed id, so we can then let the dynamically created ones come after
this highest number.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently when version 3.1 of the mx6q SDMA firmware is used we get:
[ 0.392169] imx-sdma 20ec000.sdma: unknown firmware version
[ 0.399281] imx-sdma 20ec000.sdma: initialized
Add support for it.
Based on a patch from Shengjiu Wang from the internal FSL kernel.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
While testing last patch series, I found req sock refcounting was wrong.
We must set skc_refcnt to 1 for all request socks added in hashes,
but also on request sockets created by FastOpen or syncookies.
It is tricky because we need to defer this initialization so that
future RCU lookups do not try to take a refcount on a not yet
fully initialized request socket.
Also get rid of ireq_refcnt alias.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 13854e5a60 ("inet: add proper refcounting to request sock")
Signed-off-by: David S. Miller <davem@davemloft.net>
The listener field in struct tcp_request_sock is a pointer
back to the listener. We now have req->rsk_listener, so TCP
only needs one boolean and not a full pointer.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Once we'll be able to lookup request sockets in ehash table,
we'll need to get access to listener which created this request.
This avoid doing a lookup to find the listener, which benefits
for a more solid SO_REUSEPORT, and is needed once we no
longer queue request sock into a listener private queue.
Note that 'struct tcp_request_sock'->listener could be reduced
to a single bit, as TFO listener should match req->rsk_listener.
TFO will no longer need to hold a reference on the listener.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet_reqsk_alloc() is becoming fat and should not be inlined.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
listener socket can be used to set net pointer, and will
be later used to hold a reference on listener.
Add a const qualifier to first argument (struct request_sock_ops *),
and factorize all write_pnet(&ireq->ireq_net, sock_net(sk));
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a nicer way to get the ACPI _UID.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The mediatek SoCs have GPIO controller that handle both the muxing and GPIOs.
The GPIO controller have pinmux, pull enable, pull select, direction and output high/low control.
This driver include common driver and mt8135 part.
The common driver include the pinctrl driver and GPIO driver.
The mt8135 part contain its special device data.
Signed-off-by: Hongzhou Yang <hongzhou.yang@mediatek.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
dai-link params for codec-codec links were fixed. The fixed
link between codec and another chip which may be another codec,
baseband, bluetooth codec etc may require run time configuaration
changes. This change provides an optional alsa control to select
one of the params from a list of params.
Signed-off-by: Nikesh Oswal <nikesh@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Setup new I915_GETPARAM ioctl entries for subslice total and
EU total. Userspace drivers need these values when constructing
GPGPU commands. This kernel query method is intended to replace
the PCI ID-based tables that userspace drivers currently maintain.
The kernel driver can employ fuse register reads as needed to
ensure the most accurate determination of GT config attributes.
This first became important with Cherryview in which the config
could differ between devices with the same PCI ID.
The kernel detection of these values is device-specific and not
included in this patch. Because zero is not a valid value for any of
these parameters, a value of zero is interpreted as unknown for the
device. Userspace drivers should continue to maintain ID-based tables
for older devices not supported by the new query method.
v2: Increment our I915_GETPARAM indices to fit after REVISION
which was merged ahead of us.
For: VIZ-4636
Signed-off-by: Jeff McGee <jeff.mcgee@intel.com>
Tested-by: Zhigang Gong <zhigang.gong@linux.intel.com>
Acked-by: Zhigang Gong <zhigang.gong@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Spell all the PCI IDs out to be able to quickly grep for the IDs. No
functional changes.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
[danvet: Add GT1/2 to comments to not loose that distinction.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
I have no idea about the exact rules, but this angered Dave's 32bit
rhel gcc.
Reported-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Adds a parameter which can be used with DRM_I915_GETPARAM to query the
GPU revision. The intention is to use this in Mesa to implement the
WaDisableSIMD16On3SrcInstr workaround on Skylake but only for
revision 2.
Signed-off-by: Neil Roberts <neil@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
tcp_oow_rate_limited() is hardly used in fast path, there is
no point inlining it.
Signed-of-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This big helper is called once from tcp_conn_request(), there is no
point having it in an include. Compiler will inline it anyway.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On 64bit arches, we can save 8 bytes in inet_request_sock
by moving ir_mark to fill a hole.
While we are at it, inet_request_mark() can get a const qualifier
for listener socket.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
as a follow on to patch 70006af955 ("bpf: allow eBPF access skb fields")
this patch allows 'protocol' and 'vlan_tci' fields to be accessible
from extended BPF programs.
The usage of 'protocol', 'vlan_present' and 'vlan_tci' fields is the same as
corresponding SKF_AD_PROTOCOL, SKF_AD_VLAN_TAG_PRESENT and SKF_AD_VLAN_TAG
accesses in classic BPF.
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The argument 'flags' was missing in ndo_bridge_setlink().
ndo_bridge_dellink() was missing.
Fixes: 407af3299e ("bridge: Add netlink interface to configure vlans on bridge ports")
Fixes: add511b382 ("bridge: add flags argument to ndo_bridge_setlink and ndo_bridge_dellink")
CC: Vlad Yasevich <vyasevic@redhat.com>
CC: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
more minor issues with our virtio 1.0 drivers just introduced in the
kernel.
(I would normally use my fixes branch for this, but there were a batch of them...)
Thanks,
Rusty.
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull virtio fixes from Rusty Russell:
"Not entirely surprising: the ongoing QEMU work on virtio 1.0 has
revealed more minor issues with our virtio 1.0 drivers just introduced
in the kernel.
(I would normally use my fixes branch for this, but there were a batch
of them...)"
* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
virtio_mmio: fix access width for mmio
uapi/virtio_scsi: allow overriding CDB/SENSE size
virtio_mmio: generation support
virtio_rpmsg: set DRIVER_OK before using device
9p/trans_virtio: fix hot-unplug
virtio-balloon: do not call blocking ops when !TASK_RUNNING
virtio_blk: fix comment for virtio 1.0
virtio_blk: typo fix
virtio_balloon: set DRIVER_OK before using device
virtio_console: avoid config access from irq
virtio_console: init work unconditionally
Pull kvm fixes from Marcelo Tosatti:
"KVM bug fixes (ARM and x86)"
* git://git.kernel.org/pub/scm/virt/kvm/kvm:
arm/arm64: KVM: Keep elrsr/aisr in sync with software model
KVM: VMX: Set msr bitmap correctly if vcpu is in guest mode
arm/arm64: KVM: fix missing unlock on error in kvm_vgic_create()
kvm: x86: i8259: return initialized data on invalid-size read
arm64: KVM: Fix outdated comment about VTCR_EL2.PS
arm64: KVM: Do not use pgd_index to index stage-2 pgd
arm64: KVM: Fix stage-2 PGD allocation to have per-page refcounting
kvm: move advertising of KVM_CAP_IRQFD to common code
The mgmt.c file should be reserved purely for HCI_CHANNEL_CONTROL. The
mgmt_control() function in it is already completely generic and has a
single user in hci_sock.c. This patch moves the function there and
renames it a bit more appropriately to hci_mgmt_cmd() (as it's a command
dispatcher).
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In order to make the mgmt command handling more generic we can't have a
direct call to mgmt_init_hdev() from mgmt_control(). This patch adds a
new callback to struct hci_mgmt_chan. And sets it to point to the
mgmt_init_hdev() function for the HCI_CHANNEL_CONTROL instance.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We'll need to have access to which HCI channel a socket is bound to, in
order to manage pending mgmt commands in clean way. This patch adds a
helper for the purpose.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Some controllers allow both LE scan and BR/EDR inquiry to run at
the same time, while others allow only one, LE SCAN or BR/EDR
inquiry at given time.
Since this is specific to each controller, add a new quirk setting
that allows drivers to tell the core wether given controller can
do both LE scan and BR/EDR inquiry at same time.
Signed-off-by: Jakub Pawlowski <jpawlowski@google.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Add a tuning knob so we can adjust the dirtytime expiration timeout,
which is very useful for testing lazytime.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Jan Kara pointed out that if there is an inode which is constantly
getting dirtied with I_DIRTY_PAGES, an inode with an updated timestamp
will never be written since inode->dirtied_when is constantly getting
updated. We fix this by adding an extra field to the inode,
dirtied_time_when, so inodes with a stale dirtytime can get detected
and handled.
In addition, if we have a dirtytime inode caused by an atime update,
and there is no write activity on the file system, we need to have a
secondary system to make sure these inodes get written out. We do
this by setting up a second delayed work structure which wakes up the
CPU much more rarely compared to writeback_expire_centisecs.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Provide the KVM_S390_GET_SKEYS and KVM_S390_SET_SKEYS ioctl which can be used
to get/set guest storage keys. This functionality is needed for live migration
of s390 guests that use storage keys.
Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The Store System Information (STSI) instruction currently collects all
information it relays to the caller in the kernel. Some information,
however, is only available in user space. An example of this is the
guest name: The kernel always sets "KVMGuest", but user space knows the
actual guest name.
This patch introduces a new exit, KVM_EXIT_S390_STSI, guarded by a
capability that can be enabled by user space if it wants to be able to
insert such data. User space will be provided with the target buffer
and the requested STSI function code.
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
On s390, we've got to make sure to hold the IPTE lock while accessing
logical memory. So let's add an ioctl for reading and writing logical
memory to provide this feature for userspace, too.
The maximum transfer size of this call is limited to 64kB to prevent
that the guest can trigger huge copy_from/to_user transfers. QEMU
currently only requests up to one or two pages so far, so 16*4kB seems
to be a reasonable limit here.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
An unintended consequence of commit 42ac9bd18d ("vfio: initialize
the virqfd workqueue in VFIO generic code") is that the vfio module
is renamed to vfio_core so that it can include both vfio and virqfd.
That's a user visible change that may break module loading scritps
and it imposes eventfd support as a dependency on the core vfio code,
which it's really not. virqfd is intended to be provided as a service
to vfio bus drivers, so instead of wrapping it into vfio.ko, we can
make it a stand-alone module toggled by vfio bus drivers. This has
the additional benefit of removing initialization and exit from the
core vfio code.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Since the last and the only user of this driver is converted to use dw_dmac we
can remove driver from the tree.
Moreover, besides the driver is unmaintained a long time, it serves for the
DesignWare DMA IP, for which we have already driver in the tree.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Palmas driver is used to cater to even TPS659038 but TPS659038 does not have
REGEN3 resource. Adding another field in the driver data to check on that.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The register offset for REGEN2_CTRL in different for TPS659038 chip as when
compared with other Palmas family PMICs. In the case of TPS659038 the wrong
offset pointed to PLLEN_CTRL and was causing a hang. Correcting the same.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This patch moves the xilinx_dma.h header file
to the include/linux/dma.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There is a notifier that handles live patches for coming and going modules.
It takes klp_mutex lock to avoid races with coming and going patches but
it does not keep the lock all the time. Therefore the following races are
possible:
1. The notifier is called sometime in STATE_MODULE_COMING. The module
is visible by find_module() in this state all the time. It means that
new patch can be registered and enabled even before the notifier is
called. It might create wrong order of stacked patches, see below
for an example.
2. New patch could still see the module in the GOING state even after
the notifier has been called. It will try to initialize the related
object structures but the module could disappear at any time. There
will stay mess in the structures. It might even cause an invalid
memory access.
This patch solves the problem by adding a boolean variable into struct module.
The value is true after the coming and before the going handler is called.
New patches need to be applied when the value is true and they need to ignore
the module when the value is false.
Note that we need to know state of all modules on the system. The races are
related to new patches. Therefore we do not know what modules will get
patched.
Also note that we could not simply ignore going modules. The code from the
module could be called even in the GOING state until mod->exit() finishes.
If we start supporting patches with semantic changes between function
calls, we need to apply new patches to any still usable code.
See below for an example.
Finally note that the patch solves only the situation when a new patch is
registered. There are no such problems when the patch is being removed.
It does not matter who disable the patch first, whether the normal
disable_patch() or the module notifier. There is nothing to do
once the patch is disabled.
Alternative solutions:
======================
+ reject new patches when a patched module is coming or going; this is ugly
+ wait with adding new patch until the module leaves the COMING and GOING
states; this might be dangerous and complicated; we would need to release
kgr_lock in the middle of the patch registration to avoid a deadlock
with the coming and going handlers; also we might need a waitqueue for
each module which seems to be even bigger overhead than the boolean
+ stop modules from entering COMING and GOING states; wait until modules
leave these states when they are already there; looks complicated; we would
need to ignore the module that asked to stop the others to avoid a deadlock;
also it is unclear what to do when two modules asked to stop others and
both are in COMING state (situation when two new patches are applied)
+ always register/enable new patches and fix up the potential mess (registered
patches order) in klp_module_init(); this is nasty and prone to regressions
in the future development
+ add another MODULE_STATE where the kallsyms are visible but the module is not
used yet; this looks too complex; the module states are checked on "many"
locations
Example of patch stacking breakage:
===================================
The notifier could _not_ _simply_ ignore already initialized module objects.
For example, let's have three patches (P1, P2, P3) for functions a() and b()
where a() is from vmcore and b() is from a module M. Something like:
a() b()
P1 a1() b1()
P2 a2() b2()
P3 a3() b3(3)
If you load the module M after all patches are registered and enabled.
The ftrace ops for function a() and b() has listed the functions in this
order:
ops_a->func_stack -> list(a3,a2,a1)
ops_b->func_stack -> list(b3,b2,b1)
, so the pointer to b3() is the first and will be used.
Then you might have the following scenario. Let's start with state when patches
P1 and P2 are registered and enabled but the module M is not loaded. Then ftrace
ops for b() does not exist. Then we get into the following race:
CPU0 CPU1
load_module(M)
complete_formation()
mod->state = MODULE_STATE_COMING;
mutex_unlock(&module_mutex);
klp_register_patch(P3);
klp_enable_patch(P3);
# STATE 1
klp_module_notify(M)
klp_module_notify_coming(P1);
klp_module_notify_coming(P2);
klp_module_notify_coming(P3);
# STATE 2
The ftrace ops for a() and b() then looks:
STATE1:
ops_a->func_stack -> list(a3,a2,a1);
ops_b->func_stack -> list(b3);
STATE2:
ops_a->func_stack -> list(a3,a2,a1);
ops_b->func_stack -> list(b2,b1,b3);
therefore, b2() is used for the module but a3() is used for vmcore
because they were the last added.
Example of the race with going modules:
=======================================
CPU0 CPU1
delete_module() #SYSCALL
try_stop_module()
mod->state = MODULE_STATE_GOING;
mutex_unlock(&module_mutex);
klp_register_patch()
klp_enable_patch()
#save place to switch universe
b() # from module that is going
a() # from core (patched)
mod->exit();
Note that the function b() can be called until we call mod->exit().
If we do not apply patch against b() because it is in MODULE_STATE_GOING,
it will call patched a() with modified semantic and things might get wrong.
[jpoimboe@redhat.com: use one boolean instead of two]
Signed-off-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
