During CPU online/offline testing on a large system, one of the
processors got stuck after the message "bad: scheduling from the
idle thread!".  The problem is that acpi_cpu_soft_notify() calls
acpi_bus_get_device() for all action types.  CPU_STARTING and
CPU_DYING do not allow the notify handlers to sleep.  However,
acpi_bus_get_device() can sleep in acpi_ut_acquire_mutex().

Change acpi_cpu_soft_notify() to return immediately for CPU_STARTING
and CPU_DYING as they have no action in this handler.
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We already have a macro for PREFIX of "ACPI: " in
drivers/acpi/internal.h, so remove the duplicate ones
in ACPI drivers when internal.h is included.
Signed-off-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Use ACPI_COMPANION() to get an ACPI device instead of
acpi_bus_get_device() in the processor driver.
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
[rjw: Changelog]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Function acpi_processor_load_module() used by the ACPI processor
driver can only really work if the acpi-cpufreq module is available
when acpi_processor_start() is executed which usually is not the case
for systems loading the processor driver module from an initramfs.

Moreover, that used to be a hackish workaround for module autoloading
issues, but udev loads acpi-cpufreq just fine nowadays, so that
function isn't really necessary any more.  For this reason, drop
acpi_processor_load_module() entirely.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Fixed a brace coding style issue. (Brace not on the good line)
Signed-off-by: NMathieu Rhéaume <mathieu@codingrhemes.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

acpi_processor_get_limit_info() is only called in the __acpi_processor_start()
and what it does actually is just to check pr->flags.throttling and set limit.
The pr pointer has been checked in the __acpi_processor_start() before
acpi_processor_get_limit_info() being called. It doesn't make sense still to
keep it as a function. So move code to __acpi_processor_start() and remove
acpi_processor_get_limit_info().
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Acked-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

It is quite some time that this one has been deprecated.
Get rid of it.

Should some really important user be overseen, it may be reverted and
the userspace program worked on first, but it is time to do something
to get rid of this old stuff...
Signed-off-by: NThomas Renninger <trenn@suse.de>
Acked-by: NMatthew Garrett <matthew.garrett@nebula.com>
Acked-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the drivers/acpi uses of the __cpuinit macros
from all C files.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Len Brown <lenb@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: linux-acpi@vger.kernel.org
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

ACPI_PROCESSOR_FILE_INFO, ACPI_PROCESSOR_FILE_THROTTLING and
ACPI_PROCESSOR_FILE_LIMIT are used for procfs, but this feature was removed
in commit d09fe555 (ACPI processor: remove deprecated ACPI procfs I/F) long
ago. So, these macros should also be removed.

ACPI_PROCESSOR_LIMIT_USER and ACPI_PROCESSOR_LIMIT_THERMAL are not used
by any code, remove them too.
Signed-off-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit ac212b69 (ACPI / processor: Use common hotplug infrastructure)
forgot about initializing the per-CPU 'processors' variables which
lead to ACPI cpuidle failure to use C-states and caused boot slowdown
on multi-CPU machines.

Fix the problem by adding per_cpu(processors, pr->id) initialization
to acpi_processor_add() and add make acpi_processor_remove() clean it
up as appropriate.

Also modify acpi_processor_stop() so that it doesn't clear
per_cpu(processors, pr->id) on processor driver removal which would
then cause problems to happen when the driver is loaded again.

This version of the patch contains fixes from Yinghai Lu.
Reported-and-tested-by: NYinghai Lu <yinghai@kernel.org>
Reported-and-tested-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Split the ACPI processor driver into two parts, one that is
non-modular, resides in the ACPI core and handles the enumeration
and hotplug of processors and one that implements the rest of the
existing processor driver functionality.

The non-modular part uses an ACPI scan handler object to enumerate
processors on the basis of information provided by the ACPI namespace
and to hook up with the common ACPI hotplug infrastructure.  It also
populates the ACPI handle of each processor device having a
corresponding object in the ACPI namespace, which allows the driver
proper to bind to those devices, and makes the driver bind to them
if it is readily available (i.e. loaded) when the scan handler's
.attach() routine is running.

There are a few reasons to make this change.

First, switching the ACPI processor driver to using the common ACPI
hotplug infrastructure reduces code duplication and size considerably,
even though a new file is created along with a header comment etc.

Second, since the common hotplug code attempts to offline devices
before starting the (non-reversible) removal procedure, it will abort
(and possibly roll back) hot-remove operations involving processors
if cpu_down() returns an error code for one of them instead of
continuing them blindly (if /sys/firmware/acpi/hotplug/force_remove
is unset).  That is a more desirable behavior than what the current
code does.

Finally, the separation of the scan/hotplug part from the driver
proper makes it possible to simplify the driver's .remove() routine,
because it doesn't need to worry about the possible cleanup related
to processor removal any more (the scan/hotplug part is responsible
for that now) and can handle device removal and driver removal
symmetricaly (i.e. as appropriate).

Some user-visible changes in sysfs are made (for example, the
'sysdev' link from the ACPI device node to the processor device's
directory is gone and a 'physical_node' link is present instead
and a corresponding 'firmware_node' is present in the processor
device's directory, the processor driver is now visible under
/sys/bus/cpu/drivers/ and bound to the processor device), but
that shouldn't affect the functionality that users care about
(frequency scaling, C-states and thermal management).

Tested on my venerable Toshiba Portege R500.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NToshi Kani <toshi.kani@hp.com>

The system suspend routine of the ACPI processor driver saves
the BUS_MASTER_RLD register and its resume routine restores it.
However, there can be only one such register in the system and it
really should be saved after non-boot CPUs have been offlined and
restored before they are put back online during resume.

For this reason, move the saving and restoration of BUS_MASTER_RLD
to syscore suspend and syscore resume, respectively, and drop the no
longer necessary suspend/resume callbacks from the ACPI processor
driver.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

pr->id is u32 which never < 0, so remove the redundant pr->id < 0
check from acpi_processor_add().

[rjw: Changelog]
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The node will be offlined when all memory/cpu on the node is hotremoved.
So we should try offline the node when hotremoving a cpu on the node.
Signed-off-by: NWen Congyang <wency@cn.fujitsu.com>
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This changeset is aimed at fixing a few different but related
problems in the ACPI hotplug infrastructure.

First of all, since notify handlers may be run in parallel with
acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device()
and some of them are installed for ACPI handles that have no struct
acpi_device objects attached (i.e. before those objects are created),
those notify handlers have to take acpi_scan_lock to prevent races
from taking place (e.g. a struct acpi_device is found to be present
for the given ACPI handle, but right after that it is removed by
acpi_bus_trim() running in parallel to the given notify handler).
Moreover, since some of them call acpi_bus_scan() and
acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock
should be acquired by the callers of these two funtions rather by
these functions themselves.

For these reasons, make all notify handlers that can handle device
addition and eject events take acpi_scan_lock and remove the
acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim().
Accordingly, update all of their users to make sure that they
are always called under acpi_scan_lock.

Furthermore, since eject operations are carried out asynchronously
with respect to the notify events that trigger them, with the help
of acpi_bus_hot_remove_device(), even if notify handlers take the
ACPI scan lock, it still is possible that, for example,
acpi_bus_trim() will run between acpi_bus_hot_remove_device() and
the notify handler that scheduled its execution and that
acpi_bus_trim() will remove the device node passed to
acpi_bus_hot_remove_device() for ejection.  In that case, the struct
acpi_device object obtained by acpi_bus_hot_remove_device() will be
invalid and not-so-funny things will ensue.  To protect agaist that,
make the users of acpi_bus_hot_remove_device() run get_device() on
ACPI device node objects that are about to be passed to it and make
acpi_bus_hot_remove_device() run put_device() on them and check if
their ACPI handles are not NULL (make acpi_device_unregister() clear
the device nodes' ACPI handles for that check to work).

Finally, observe that acpi_os_hotplug_execute() actually can fail,
in which case its caller ought to free memory allocated for the
context object to prevent leaks from happening.  It also needs to
run put_device() on the device node that it ran get_device() on
previously in that case.  Modify the code accordingly.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>

The second argument of ACPI driver .remove() operation is only used
by the ACPI processor driver and the value passed to that driver
through it is always available from the given struct acpi_device
object's removal_type field.  For this reason, the second ACPI driver
.remove() argument is in fact useless, so drop it.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NJiang Liu <jiang.liu@huawei.com>
Acked-by: NToshi Kani <toshi.kani@hp.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>

The only difference between acpi_bus_scan() and acpi_bus_add() is the
invocation of acpi_update_all_gpes() in the latter which in fact is
unnecessary, because acpi_update_all_gpes() has already been called
by acpi_scan_init() and the way it is implemented guarantees the next
invocations of it to do nothing.

For this reason, drop acpi_bus_add() and make all its callers use
acpi_bus_scan() directly instead of it.  Additionally, rearrange the
code in acpi_scan_init() slightly to improve the visibility of the
acpi_update_all_gpes() call in there.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>

Should use acpi_device pointer directly instead of use handle and
get the device pointer again later.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The callers of acpi_bus_add() usually assume that if it has
succeeded, then a struct acpi_device object has been attached to
the handle passed as the first argument.  Unfortunately, however,
this assumption is wrong, because acpi_bus_scan(), and acpi_bus_add()
too as a result, may return a pointer to a different struct
acpi_device object on success (it may be an object corresponding to
one of the descendant ACPI nodes in the namespace scope below that
handle).

For this reason, the callers of acpi_bus_add() who care about
whether or not a struct acpi_device object has been created for
its first argument need to check that using acpi_bus_get_device()
anyway, so the second argument of acpi_bus_add() is not really
useful for them.  The same observation applies to acpi_bus_scan()
executed directly from acpi_scan_init().

Therefore modify the relevant callers of acpi_bus_add() to check the
existence of the struct acpi_device in question with the help of
acpi_bus_get_device() and drop the no longer necessary second
argument of acpi_bus_add().  Accordingly, modify acpi_scan_init() to
use acpi_bus_get_device() to get acpi_root and drop the no longer
needed second argument of acpi_bus_scan().
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NToshi Kani <toshi.kani@hp.com>

Notice that acpi_bus_add() uses only 2 of its 4 arguments and
redefine its header to match the body.  Update all of its callers as
necessary and observe that this leads to quite a number of removed
lines of code (Linus will like that).

Add a kerneldoc comment documenting acpi_bus_add() and wonder how
its callers make wrong assumptions about the second argument (make
note to self to take care of that later).
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NToshi Kani <toshi.kani@hp.com>

Updated CPU hotplug error messages with acpi_handle_<level>(),
dev_<level>() and pr_<level>().  Modified some messages for
clarity.  Added error status / id info to the messages where
needed.
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Tested-by: NVijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Added support of CPU hot-remove via an ACPI eject notification.
It calls acpi_bus_hot_remove_device(), which shares the same code
path with the sysfs eject operation.  acpi_os_hotplug_execute()
runs the hot-remove operation in kacpi_hotplug_wq and serializes
it between ACPI hot-remove and sysfs eject requests.
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Reviewed-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Tested-by: NIgorMammedov <imammedo@redhat.com>
Tested-by: NVijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com>
Tested-by: NPrarit Bhargava <prarit@redhat.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Even if acpi_processor_handle_eject() offlines cpu, there is a chance
to online the cpu after that. So the patch closes the window by using
get/put_online_cpus().

Why does the patch change _cpu_up() logic?

The patch cares the race of hot-remove cpu and _cpu_up(). If the patch
does not change it, there is the following race.

hot-remove cpu                         |  _cpu_up()
------------------------------------- ------------------------------------
call acpi_processor_handle_eject()     |
     call cpu_down()                   |
     call get_online_cpus()            |
                                       | call cpu_hotplug_begin() and stop here
     call arch_unregister_cpu()        |
     call acpi_unmap_lsapic()          |
     call put_online_cpus()            |
                                       | start and continue _cpu_up()
     return acpi_processor_remove()    |
continue hot-remove the cpu            |

So _cpu_up() can continue to itself. And hot-remove cpu can also continue
itself. If the patch changes _cpu_up() logic, the race disappears as below:

hot-remove cpu                         | _cpu_up()
-----------------------------------------------------------------------
call acpi_processor_handle_eject()     |
     call cpu_down()                   |
     call get_online_cpus()            |
                                       | call cpu_hotplug_begin() and stop here
     call arch_unregister_cpu()        |
     call acpi_unmap_lsapic()          |
          cpu's cpu_present is set     |
          to false by set_cpu_present()|
     call put_online_cpus()            |
                                       | start _cpu_up()
                                       | check cpu_present() and return -EINVAL
     return acpi_processor_remove()    |
continue hot-remove the cpu            |
Signed-off-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reviewed-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Reviewed-by: NToshi Kani <toshi.kani@hp.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We handle NOTIFY_THROTTLING so don't then fall through to unsupported event.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The 'errata' variable is a global variable which is set to zero,
no need to do that with a memset in the init function.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

The 'device' parameter is not used neither in acpi_processor_power_init
and acpi_processor_power_exit. This patch removes it.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

In commit 99b72508 "ACPI processor hotplug: Delay acpi_processor_start()
call for hotplugged cores", acpi_processor_hotplug(pr) was wrongly replaced
by acpi_processor_cst_has_changed() inside the acpi_cpu_soft_notify(). This
patch will restore it back, fixing the tick_broadcast_mask regression:
	https://lkml.org/lkml/2012/7/30/169Signed-off-by: NFeng Tang <feng.tang@intel.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: <stable@vger.kernel.org> # 3.3+
Reviewed-by: NRafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: NDeepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

When the system is booted with some cpus offline, the idle
driver is not initialized. When a cpu is set online, the
acpi code call the intel idle init function. Unfortunately
this code introduce a dependency between intel_idle and acpi.

This patch is intended to remove this dependency by using the
notifier of intel_idle. This patch has the benefit of
encapsulating the intel_idle driver and remove some exported
functions.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Make the ACPI processor driver define its PM callbacks through
a struct dev_pm_ops object rather than by using legacy PM hooks
in struct acpi_device_ops.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

Changed acpi_processor_hotplug_notify() to call ACPI _OST method
when ACPI CPU hotplug operation has completed.
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

The function acpi_processor_add is stored in the ops.add field of a
acpi_driver structure.  This function is then called in
acpi_bus_driver_init.  On failure, this function clears the field
device->driver_data, but does not free its contents.  Thus the free has to
be done by the add function.  In acpi_processor_add, the corresponding
value is pr.  This value is currently freed on failure before storing it in
device->driver_data, but not after.  This free is added in the error
handling code at the end of the function.  The per_cpu variable
processors is also cleared so that it does not refer to a dangling pointer.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: NDeepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

acpi_processor_install_hotplug_notify() registers processor objects to
receive ACPI CPU hotplug event notifications. This patch additionally
registers processor device objects (ACPI0007) to receive the notifications
as well.
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Reviewed-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: NDavid Howells <dhowells@redhat.com>

When checking driver-core tree, found crazying warnings on my setups.

[  216.025849] calling  acpi_processor_init+0x0/0x81 @ 1
[  216.045332] ACPI: Requesting acpi_cpufreq
[  216.047454] Monitor-Mwait will be used to enter C-1 state
[  216.047912] Monitor-Mwait will be used to enter C-3 state
[  216.065270] ACPI: acpi_idle registered with cpuidle
[  216.068241] kobject (ffff8870364a1940): tried to init an initialized object, something is seriously wrong.
[  216.085287] Pid: 1, comm: swapper/0 Not tainted 3.3.0-rc2-tip-yh-02428-ge663840-dirty #247
[  216.105041] Call Trace:
[  216.105192]  [<ffffffff813a9c06>] kobject_init+0x33/0x83
[  216.124880]  [<ffffffff813aa1f8>] kobject_init_and_add+0x23/0x57
[  216.125158]  [<ffffffff819f3a08>] cpuidle_add_sysfs+0x49/0x62
[  216.144850]  [<ffffffff819f2a28>] __cpuidle_register_device+0xe6/0x10e
[  216.145182]  [<ffffffff819f2ea4>] cpuidle_register_device+0x25/0x4d
[  216.164912]  [<ffffffff81cb5774>] acpi_processor_power_init+0x13e/0x16c
[  216.165205]  [<ffffffff81427620>] ? acpi_processor_get_throttling_info+0x128/0x158
[  216.185012]  [<ffffffff81c68ae5>] acpi_processor_start+0x62/0x11d
[  216.204861]  [<ffffffff81cb55ff>] acpi_processor_add+0x1b0/0x1e7
[  216.205144]  [<ffffffff81402a7e>] acpi_device_probe+0x4e/0x11c
[  216.225063]  [<ffffffff8148f0e7>] really_probe+0x99/0x126
[  216.225328]  [<ffffffff8148f2a3>] driver_probe_device+0x3b/0x56
[  216.244846]  [<ffffffff8148f31d>] __driver_attach+0x5f/0x82
[  216.245101]  [<ffffffff8148f2be>] ? driver_probe_device+0x56/0x56
[  216.264668]  [<ffffffff8148db80>] bus_for_each_dev+0x5c/0x88
[  216.264942]  [<ffffffff8148eea7>] driver_attach+0x1e/0x20
[  216.284639]  [<ffffffff8148eaec>] bus_add_driver+0xca/0x21d
[  216.284903]  [<ffffffff81095827>] ? local_clock+0xf/0x3c
[  216.304580]  [<ffffffff82814177>] ? acpi_fan_init+0x18/0x18
[  216.304849]  [<ffffffff8148f79b>] driver_register+0x91/0xfe
[  216.324545]  [<ffffffff82814177>] ? acpi_fan_init+0x18/0x18
[  216.324813]  [<ffffffff81403705>] acpi_bus_register_driver+0x43/0x45
[  216.344563]  [<ffffffff828141a7>] acpi_processor_init+0x30/0x81
[  216.344845]  [<ffffffff82814177>] ? acpi_fan_init+0x18/0x18
[  216.364590]  [<ffffffff810001e7>] do_one_initcall+0x57/0x134
[  216.364868]  [<ffffffff827e6f8c>] kernel_init+0x146/0x1c0
[  216.384512]  [<ffffffff81d03aa4>] kernel_thread_helper+0x4/0x10
[  216.384819]  [<ffffffff81cfbb5d>] ? retint_restore_args+0xe/0xe
[  216.404578]  [<ffffffff827e6e46>] ? start_kernel+0x3ab/0x3ab
[  216.424530]  [<ffffffff81d03aa0>] ? gs_change+0xb/0xb
[  216.424793] ------------[ cut here ]------------
[  216.425038] WARNING: at fs/sysfs/dir.c:502 sysfs_add_one+0x97/0xab()
[  216.444480] Hardware name: Sun Fire X4800
[  216.444668] sysfs: cannot create duplicate filename '/devices/system/cpu/cpu0/cpuidle'
...

It turns out acpi_processor_power_init() get called two time in acpi_processor_add and acpi_processor_start.

Found several lines are duplicated in those two functions even related commit move them.

The related patches are ok.  Not sure how it could happen, looks like git problem.

-v2: add back acpi_processor_load_module(pr) to acpi_processor_load_start
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: NThomas Renninger <trenn@suse.de>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Those lines have two copies.

Not sure how it could happen, looks like git problem.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Renninger <trenn@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Those lines have two copies.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Thomas Renninger <trenn@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The only left over hole in automatic cpufreq driver loading was the loading
of ACPI cpufreq. This driver should be loaded when ACPI supports a _PDC
method and the CPU vendor wants to use acpi cpufreq.

Simply add a request module call to the acpi processor core driver
when this is true. This seems like the simplest solution for this.

Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NThomas Renninger <trenn@suse.de>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Delay the setting up of features (cpuidle, throttling by calling
acpi_processor_start()) to the time when the hotplugged
core got onlined the first time and got fully
initialized.
Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NLen Brown <len.brown@intel.com>

No functional change.

This is needed because:
When a CPU gets hotplugged, it's totally uninitialized
and offline. cpuinfo_x86 struct (cpu_data(cpu)) is mostly
zero (CPU feature flags, model, family,..).

When a CPU gets hotplugged, struct processor is alloc'd,
some sysfs files are set up but acpi_processor_add()
must not try to access a MSR on this CPU or try to read
out CPU feature,family, etc.

This must be done in acpi_processor_start().
The next patch will delay the call of acpi_processor_start()
for physically hotpluggedcores, to the time when they are onlined
the first time. There it is safe then to access cpu_data(cpu)
cpuinfo_x86 struct or access MSRs which is needed to
set up cpuidle, throttling and other features.

Tested and
Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NLen Brown <len.brown@intel.com>

V2: Fix typo: pr->handle -> pr, here: acpi_processor_hotadd_init(pr)

This is a very small part taken from patches which afaik
are coming from Yunhong Jiang (for a Xen not a Linus repo?).

Cleanup only: no functional change.

Advantage (beside cleanup) is that other data of the pr (acpi_processor) struct
in the acpi_processor_hotadd_init() is needed later, for example a newly
introduced flag:
pr->flags.need_hotplug_init
Signed-off-by: NThomas Renninger <trenn@suse.de>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Jiang, Yunhong <yunhong.jiang@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>