ACPI / LPSS: allow to use specific PM domain during ->probe()

The LPSS DMA controller would like to use the specific PM domain callbacks
during early stage, namely in ->probe(). This patch moves the specific PM
domain assignment early to be accessible during a whole life time of the device
in the system.

Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Scott Ashcroft <scott.ashcroft@talk21.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / LPSS: introduce a 'proxy' device to power on LPSS for DMA

The LPSS DMA controller does not have _PS0 and _PS3 methods. Moreover it can be
powered off automatically whenever the last LPSS device goes down. In case of
no power any access to the DMA controller will hang the system. The behaviour
is reproduced on some HP laptops based on Intel Bay Trail [1] as well as on
Asus T100 transformer.

This patch introduces a so called 'proxy' device that has the knobs to handle a
power of the LPSS island. When the system needs to program the DMA controller
it calls to the ACPI LPSS power domain callbacks that wake or suspend the
'proxy' device.

[1] http://www.spinics.net/lists/dmaengine/msg01514.html

Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Scott Ashcroft <scott.ashcroft@talk21.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
dmaengine: dw: enable runtime PM

On runtime PM aware platforms the DMA have to manage its own power state. This
patch enables runtime PM support and applies necessary calls wherever it's
needed.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Tested-by: Scott Ashcroft <scott.ashcroft@talk21.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / OSL: Add IRQ handler flushing support in the OSL.

It is possible that a GPE handler or a fixed event handler still accessed
after removing the handlers by invoking acpi_remove_gpe_handler() or
acpi_remove_fixed_event_handler(), this possibility can crash OPSM after a
module removal. In the Linux kernel, though all other GPE drivers are not
modules, since the IPMI_SI (ipmi_si_intf.c) can be compiled as a module, we
still need to consider a solution for this issue when the driver switches
to ACPI_GPE_RAW_HANDLER mode in order to invoke GPE APIs.

ACPICA expects acpi_os_wait_events_complete() to be invoked after GPE
disabling so that OSPM can ensure all running GPE handlers have exitted.
But currently acpi_os_wait_events_complete() can only flush _Lxx/_Exx
evaluation work queue and this philosophy cannot work for drivers that have
installed a dedicated GPE handler.

The only way to protect a callback is to perform some state holders
(reference count, state machine) before invoking the callback. Then this
issue can only be fixed by the following means:
1. Flush GPE in ACPICA before invoking the GPE handler. But currently,
   there is no such implementation in acpi_ev_gpe_dispatch().
2. Flush GPE in ACPICA OSL before invoking the SCI handler. But currently,
   there is no such implementation in acpi_irq().
3. Flush IRQ in OSPM IRQ layer before invoking the IRQ handler. In Linus
   kernel, this can be done by synchronize_irq().
4. Flush scheduling in OSPM vector entry layer before invoking the vector.
   In Linux, this can be done by synchronize_sched().

Since ACPICA expects the GPE handlers to be flushed by the ACPICA OSL or
the GPE drivers. If it is implemented by the GPE driver, we should see
synchronize_irq()/synchronize_sched() invoked in such drivers. If it is
implemented by the ACPICA OSL, ACPICA currently provides
acpi_os_wait_events_complete() hook to achieve this. After the following
commit:
  Commit: 69c841b6dd8313c9a673246cc0e2535174272cab
  Author: Lv Zheng <lv.zheng@intel.com>
  Subject: ACPICA: Update use of acpi_os_wait_events_complete interface.
The OSL acpi_os_wait_events_complete() is invoked after a GPE handler is
removed from acpi_remove_gpe_handler() or a fixed event handler is removed
from acpi_remove_fixed_event_handler(). Thus it is possible to implement
GPE handler flushing using this ACPICA OSL now. So the solution 1 is
currently not taken into account.

By examining the IPMI_SI driver, we noticed that the IPMI_SI driver:
1. Uses free_irq() to flush non GPE based IRQ handlers, in free_irq(),
   synchronize_irq() is invoked, and
2. Uses acpi_remove_gpe_handler() to flush GPE based IRQ handlers, for such
   IRQ handlers, there is no synchronize_irq() invoked.
Since there isn't synchronize_sched() implemented for this driver, from the
driver's perspective, acpi_remove_gpe_handler() should have properly
flushed the GPE handlers for it. Since the driver doesn't invoke
synchronize_irq(), the solution 3 is not what the drivers expect.

This patch implements solution 2. But since given the fact that the GPE is
managed inside of ACPICA, and implementing the GPE flushing requires to
implement the whole GPE management code again in the OSL, instead of
flushing GPE, this patch flushes IRQ in acpi_os_wait_events_complete(). The
flushing could last longer than expected as though the target GPE/fixed
event that is removed can be fastly flushed, other GPEs/fix events can still
be issued during the flushing period.

This patch fixes this issue by invoking synchronize_hardirq() in
acpi_os_wait_events_complete(). The reason why we don't invoke
synchronize_irq() is: currently ACPICA is not threaded IRQ capable and the
only difference between synchronize_irq() and synchronize_hardirq() is
synchronize_irq() also flushes threaded IRQ handlers. Thus using
synchronize_hardirq() can help to reduce the overall synchronization time
for the current ACPICA implementation.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: linux-acpi@vger.kernel.org
Cc: devel@acpica.org
Cc: openipmi-developer@lists.sourceforge.net
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
x86: Add support for Intel HWP feature detection.

Add support of Hardware Managed Performance States (HWP) described in Volume 3
section 14.4 of the SDM.

One bit CPUID.06H:EAX[bit 7] expresses the presence of the HWP feature on
the processor. The remaining bits CPUID.06H:EAX[bit 8-11] denote the
presense of various HWP features.

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
intel_pstate: Add support for HWP

Add support of Hardware Managed Performance States (HWP) described in Volume 3
section 14.4 of the SDM.

With HWP enbaled intel_pstate will no longer be responsible for selecting P
states for the processor. intel_pstate will continue to register to
the cpufreq core as the scaling driver for CPUs implementing
HWP. In HWP mode intel_pstate provides three functions reporting
frequency to the cpufreq core, support for the set_policy() interface
from the core and maintaining the intel_pstate sysfs interface in
/sys/devices/system/cpu/intel_pstate.  User preferences expressed via
the set_policy() interface or the sysfs interface are forwared to the
CPU via the HWP MSR interface.

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
intel_pstate: Add CPUID for BDW-H CPU

Add BDW-H to the list of supported processors.

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
block: blk-merge: fix blk_recount_segments()

For cloned bio, bio->bi_vcnt can't be used at all, and we
have resort to bio_segments() to figure out how many
segment there are in the bio.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
ACPI / EC: Introduce STARTED/STOPPED flags to replace BLOCKED flag.

By using the 2 flags, we can indicate an inter-mediate state where the
current transactions should be completed while the new transactions should
be dropped.

The comparison of the old flag and the new flags:
  Old			New
  about to set BLOCKED	STOPPED set / STARTED set
  BLOCKED set		STOPPED clear / STARTED clear
  BLOCKED clear		STOPPED clear / STARTED set
The new period is between the point where we are about to set BLOCKED and
the point when the BLOCKED is set. The GPE is disabled during this period.
The new flags allow us to add acpi_ec_stopped() check to only check with
STOPPED flag to implement transaction flushing. This is not done in this
patch.

No functional changes except that after applying this patch, the GPE
enabling/disabling is protected by the EC specific lock. We can do this
because of recent ACPICA GPE API enhancement. This is reasonable as the GPE
disabling/enabling state should only be determined by the EC driver's state
machine which is protected by the EC spinlock.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / EC: Enhance the checks to apply to QR_EC transactions.

Currently a check is applied to new transactions, but QR_EC transactions
are not included. This patch merges the code path to make the check also
applying to the QR_EC transactions.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / EC: Add reference counting for query handlers.

This patch adds reference counting for query handlers in order to eliminate
kmalloc()/kfree() usage.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Steffen Weber <steffen.weber@gmail.com>
Tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / EC: Add command flushing support.

This patch implements command flushing support. It's better to wait all
command transactions to be completed before disabling the EC GPE when the
system is going to be suspended. By doing so, the EC hardware can be
ensured to be in the idle state when the system is resumed.

There is a good indicator for flush support:
All acpi_ec_submit_request() is invoked after checking driver state with
acpi_ec_started() except the first one. This means all code paths can be
flushed as fast as possible by discarding the requests occurred after the
flush operation. The reference increased for such kind of code path is
wrapped by acpi_ec_submit_flushable_request().

The system suspending/resuming test result is as follows:
  ACPI : EC: +++++ Stopping EC +++++
* ACPI : EC: +++++ EC stopped +++++
  ACPI : EC: +++++ Starting EC +++++
# ACPI : EC: +++++ EC started +++++
This is performed by "switching wireless switch on/off" and "plugging power
cord in/out" frequently during the suspending/resuming. The above dmesg
shows that the EC driver is stopped during suspending (*) and is restarted
during resuming (#) correctly.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ipvs: Keep skb->sk when allocating headroom on tunnel xmit

ip_vs_prepare_tunneled_skb() ignores ->sk when allocating a new
skb, either unconditionally setting ->sk to NULL or allowing
the uninitialized ->sk from a newly allocated skb to leak through
to the caller.

This patch properly copies ->sk and increments its reference count.

Signed-off-by: Calvin Owens <calvinowens@fb.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
ARM: shmobile: always build rcar setup for armv7

In a combined ARMv6/v7 kernel, the setup-rcar-gen2.c cannot
currently be compiled correctly because it uses the isb
instruction that is not available on ARMv6. Adding the
-march=armv7-a flag lets the compiler know that it is safe
to build this file for ARMv7.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Merge branch 'heads/soc-for-v3.19' into next
drm/i915: Plug memory leak in intel_shared_dpll_start_config()

The cleanup path would reset pll->new_config to NULL but wouldn't free
the allocated memory.

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
netfilter: nft_compat: use current net namespace

Instead of init_net when using xtables over nftables compat.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nft_compat: relax chain type validation

Check for nat chain dependency only, which is the one that can
actually crash the kernel. Don't care if mangle, filter and security
specific match and targets are used out of their scope, they are
harmless.

This restores iptables-compat with mangle specific match/target when
used out of the OUTPUT chain, that are actually emulated through filter
chains, which broke when performing strict validation.

Fixes: f3f5dde ("netfilter: nft_compat: validate chain type in match/target")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nft_compat: use the match->table to validate dependencies

Instead of the match->name, which is of course not relevant.

Fixes: f3f5dde ("netfilter: nft_compat: validate chain type in match/target")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nf_tables: restore synchronous object release from commit/abort

The existing xtables matches and targets, when used from nft_compat, may
sleep from the destroy path, ie. when removing rules. Since the objects
are released via call_rcu from softirq context, this results in lockdep
splats and possible lockups that may be hard to reproduce.

Patrick also indicated that delayed object release via call_rcu can
cause us problems in the ordering of event notifications when anonymous
sets are in place.

So, this patch restores the synchronous object release from the commit
and abort paths. This includes a call to synchronize_rcu() to make sure
that no packets are walking on the objects that are going to be
released. This is slowier though, but it's simple and it resolves the
aforementioned problems.

This is a partial revert of c7c32e7 ("netfilter: nf_tables: defer all
object release via rcu") that was introduced in 3.16 to speed up
interaction with userspace.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>