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    Merge tag 'pm+acpi-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm · f991fae5
    Linus Torvalds authored
    Pull power management and ACPI updates from Rafael Wysocki:
     "This time the total number of ACPI commits is slightly greater than
      the number of cpufreq commits, but Viresh Kumar (who works on cpufreq)
      remains the most active patch submitter.
    
      To me, the most significant change is the addition of offline/online
      device operations to the driver core (with the Greg's blessing) and
      the related modifications of the ACPI core hotplug code.  Next are the
      freezer updates from Colin Cross that should make the freezing of
      tasks a bit less heavy weight.
    
      We also have a couple of regression fixes, a number of fixes for
      issues that have not been identified as regressions, two new drivers
      and a bunch of cleanups all over.
    
      Highlights:
    
       - Hotplug changes to support graceful hot-removal failures.
    
         It sometimes is necessary to fail device hot-removal operations
         gracefully if they cannot be carried out completely.  For example,
         if memory from a memory module being hot-removed has been allocated
         for the kernel's own use and cannot be moved elsewhere, it's
         desirable to fail the hot-removal operation in a graceful way
         rather than to crash the kernel, but currenty a success or a kernel
         crash are the only possible outcomes of an attempted memory
         hot-removal.  Needless to say, that is not a very attractive
         alternative and it had to be addressed.
    
         However, in order to make it work for memory, I first had to make
         it work for CPUs and for this purpose I needed to modify the ACPI
         processor driver.  It's been split into two parts, a resident one
         handling the low-level initialization/cleanup and a modular one
         playing the actual driver's role (but it binds to the CPU system
         device objects rather than to the ACPI device objects representing
         processors).  That's been sort of like a live brain surgery on a
         patient who's riding a bike.
    
         So this is a little scary, but since we found and fixed a couple of
         regressions it caused to happen during the early linux-next testing
         (a month ago), nobody has complained.
    
         As a bonus we remove some duplicated ACPI hotplug code, because the
         ACPI-based CPU hotplug is now going to use the common ACPI hotplug
         code.
    
       - Lighter weight freezing of tasks.
    
         These changes from Colin Cross and Mandeep Singh Baines are
         targeted at making the freezing of tasks a bit less heavy weight
         operation.  They reduce the number of tasks woken up every time
         during the freezing, by using the observation that the freezer
         simply doesn't need to wake up some of them and wait for them all
         to call refrigerator().  The time needed for the freezer to decide
         to report a failure is reduced too.
    
         Also reintroduced is the check causing a lockdep warining to
         trigger when try_to_freeze() is called with locks held (which is
         generally unsafe and shouldn't happen).
    
       - cpufreq updates
    
         First off, a commit from Srivatsa S Bhat fixes a resume regression
         introduced during the 3.10 cycle causing some cpufreq sysfs
         attributes to return wrong values to user space after resume.  The
         fix is kind of fresh, but also it's pretty obvious once Srivatsa
         has identified the root cause.
    
         Second, we have a new freqdomain_cpus sysfs attribute for the
         acpi-cpufreq driver to provide information previously available via
         related_cpus.  From Lan Tianyu.
    
         Finally, we fix a number of issues, mostly related to the
         CPUFREQ_POSTCHANGE notifier and cpufreq Kconfig options and clean
         up some code.  The majority of changes from Viresh Kumar with bits
         from Jacob Shin, Heiko Stübner, Xiaoguang Chen, Ezequiel Garcia,
         Arnd Bergmann, and Tang Yuantian.
    
       - ACPICA update
    
         A usual bunch of updates from the ACPICA upstream.
    
         During the 3.4 cycle we introduced support for ACPI 5 extended
         sleep registers, but they are only supposed to be used if the
         HW-reduced mode bit is set in the FADT flags and the code attempted
         to use them without checking that bit.  That caused suspend/resume
         regressions to happen on some systems.  Fix from Lv Zheng causes
         those registers to be used only if the HW-reduced mode bit is set.
    
         Apart from this some other ACPICA bugs are fixed and code cleanups
         are made by Bob Moore, Tomasz Nowicki, Lv Zheng, Chao Guan, and
         Zhang Rui.
    
       - cpuidle updates
    
         New driver for Xilinx Zynq processors is added by Michal Simek.
    
         Multidriver support simplification, addition of some missing
         kerneldoc comments and Kconfig-related fixes come from Daniel
         Lezcano.
    
       - ACPI power management updates
    
         Changes to make suspend/resume work correctly in Xen guests from
         Konrad Rzeszutek Wilk, sparse warning fix from Fengguang Wu and
         cleanups and fixes of the ACPI device power state selection
         routine.
    
       - ACPI documentation updates
    
         Some previously missing pieces of ACPI documentation are added by
         Lv Zheng and Aaron Lu (hopefully, that will help people to
         uderstand how the ACPI subsystem works) and one outdated doc is
         updated by Hanjun Guo.
    
       - Assorted ACPI updates
    
         We finally nailed down the IA-64 issue that was the reason for
         reverting commit 9f29ab11 ("ACPI / scan: do not match drivers
         against objects having scan handlers"), so we can fix it and move
         the ACPI scan handler check added to the ACPI video driver back to
         the core.
    
         A mechanism for adding CMOS RTC address space handlers is
         introduced by Lan Tianyu to allow some EC-related breakage to be
         fixed on some systems.
    
         A spec-compliant implementation of acpi_os_get_timer() is added by
         Mika Westerberg.
    
         The evaluation of _STA is added to do_acpi_find_child() to avoid
         situations in which a pointer to a disabled device object is
         returned instead of an enabled one with the same _ADR value.  From
         Jeff Wu.
    
         Intel BayTrail PCH (Platform Controller Hub) support is added to
         the ACPI driver for Intel Low-Power Subsystems (LPSS) and that
         driver is modified to work around a couple of known BIOS issues.
         Changes from Mika Westerberg and Heikki Krogerus.
    
         The EC driver is fixed by Vasiliy Kulikov to use get_user() and
         put_user() instead of dereferencing user space pointers blindly.
    
         Code cleanups are made by Bjorn Helgaas, Nicholas Mazzuca and Toshi
         Kani.
    
       - Assorted power management updates
    
         The "runtime idle" helper routine is changed to take the return
         values of the callbacks executed by it into account and to call
         rpm_suspend() if they return 0, which allows us to reduce the
         overall code bloat a bit (by dropping some code that's not
         necessary any more after that modification).
    
         The runtime PM documentation is updated by Alan Stern (to reflect
         the "runtime idle" behavior change).
    
         New trace points for PM QoS are added by Sahara
         (<keun-o.park@windriver.com>).
    
         PM QoS documentation is updated by Lan Tianyu.
    
         Code cleanups are made and minor issues are addressed by Bernie
         Thompson, Bjorn Helgaas, Julius Werner, and Shuah Khan.
    
       - devfreq updates
    
         New driver for the Exynos5-bus device from Abhilash Kesavan.
    
         Minor cleanups, fixes and MAINTAINERS update from MyungJoo Ham,
         Abhilash Kesavan, Paul Bolle, Rajagopal Venkat, and Wei Yongjun.
    
       - OMAP power management updates
    
         Adaptive Voltage Scaling (AVS) SmartReflex voltage control driver
         updates from Andrii Tseglytskyi and Nishanth Menon."
    
    * tag 'pm+acpi-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits)
      cpufreq: Fix cpufreq regression after suspend/resume
      ACPI / PM: Fix possible NULL pointer deref in acpi_pm_device_sleep_state()
      PM / Sleep: Warn about system time after resume with pm_trace
      cpufreq: don't leave stale policy pointer in cdbs->cur_policy
      acpi-cpufreq: Add new sysfs attribute freqdomain_cpus
      cpufreq: make sure frequency transitions are serialized
      ACPI: implement acpi_os_get_timer() according the spec
      ACPI / EC: Add HP Folio 13 to ec_dmi_table in order to skip DSDT scan
      ACPI: Add CMOS RTC Operation Region handler support
      ACPI / processor: Drop unused variable from processor_perflib.c
      cpufreq: tegra: call CPUFREQ_POSTCHANGE notfier in error cases
      cpufreq: s3c64xx: call CPUFREQ_POSTCHANGE notfier in error cases
      cpufreq: omap: call CPUFREQ_POSTCHANGE notfier in error cases
      cpufreq: imx6q: call CPUFREQ_POSTCHANGE notfier in error cases
      cpufreq: exynos: call CPUFREQ_POSTCHANGE notfier in error cases
      cpufreq: dbx500: call CPUFREQ_POSTCHANGE notfier in error cases
      cpufreq: davinci: call CPUFREQ_POSTCHANGE notfier in error cases
      cpufreq: arm-big-little: call CPUFREQ_POSTCHANGE notfier in error cases
      cpufreq: powernow-k8: call CPUFREQ_POSTCHANGE notfier in error cases
      cpufreq: pcc: call CPUFREQ_POSTCHANGE notfier in error cases
      ...
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