1. 24 Jun, 2013 1 commit
    • Rafael J. Wysocki's avatar
      ACPI / dock / PCI: Synchronous handling of dock events for PCI devices · 21a31013
      Rafael J. Wysocki authored
      The interactions between the ACPI dock driver and the ACPI-based PCI
      hotplug (acpiphp) are currently problematic because of ordering
      issues during hot-remove operations.
      
      First of all, the current ACPI glue code expects that physical
      devices will always be deleted before deleting the companion ACPI
      device objects.  Otherwise, acpi_unbind_one() will fail with a
      warning message printed to the kernel log, for example:
      
      [  185.026073] usb usb5: Oops, 'acpi_handle' corrupt
      [  185.035150] pci 0000:1b:00.0: Oops, 'acpi_handle' corrupt
      [  185.035515] pci 0000:18:02.0: Oops, 'acpi_handle' corrupt
      [  180.013656]  port1: Oops, 'acpi_handle' corrupt
      
      This means, in particular, that struct pci_dev objects have to
      be deleted before the struct acpi_device objects they are "glued"
      with.
      
      Now, the following happens the during the undocking of an ACPI-based
      dock station:
       1) hotplug_dock_devices() invokes registered hotplug callbacks to
          destroy physical devices associated with the ACPI device objects
          depending on the dock station.  It calls dd->ops->handler() for
          each of those device objects.
       2) For PCI devices dd->ops->handler() points to
          handle_hotplug_event_func() that queues up a separate work item
          to execute _handle_hotplug_event_func() for the given device and
          returns immediately.  That work item will be executed later.
       3) hotplug_dock_devices() calls dock_remove_acpi_device() for each
          device depending on the dock station.  This runs acpi_bus_trim()
          for each of them, which causes the underlying ACPI device object
          to be destroyed, but the work items queued up by
          handle_hotplug_event_func() haven't been started yet.
       4) _handle_hotplug_event_func() queued up in step 2) are executed
          and cause the above failure to happen, because the PCI devices
          they handle do not have the companion ACPI device objects any
          more (those objects have been deleted in step 3).
      
      The possible breakage doesn't end here, though, because
      hotplug_dock_devices() may return before at least some of the
      _handle_hotplug_event_func() work items spawned by it have a
      chance to complete and then undock() will cause _DCK to be
      evaluated and that will cause the devices handled by the
      _handle_hotplug_event_func() to go away possibly while they are
      being accessed.
      
      This means that dd->ops->handler() for PCI devices should not point
      to handle_hotplug_event_func().  Instead, it should point to a
      function that will do the work of _handle_hotplug_event_func()
      synchronously.  For this reason, introduce such a function,
      hotplug_event_func(), and modity acpiphp_dock_ops to point to
      it as the handler.
      
      Unfortunately, however, this is not sufficient, because if the dock
      code were not changed further, hotplug_event_func() would now
      deadlock with hotplug_dock_devices() that called it, since it would
      run unregister_hotplug_dock_device() which in turn would attempt to
      acquire the dock station's hp_lock mutex already acquired by
      hotplug_dock_devices().
      
      To resolve that deadlock use the observation that
      unregister_hotplug_dock_device() won't need to acquire hp_lock
      if PCI bridges the devices on the dock station depend on are
      prevented from being removed prematurely while the first loop in
      hotplug_dock_devices() is in progress.
      
      To make that possible, introduce a mechanism by which the callers of
      register_hotplug_dock_device() can provide "init" and "release"
      routines that will be executed, respectively, during the addition
      and removal of the physical device object associated with the
      given ACPI device handle.  Make acpiphp use two new functions,
      acpiphp_dock_init() and acpiphp_dock_release(), that call
      get_bridge() and put_bridge(), respectively, on the acpiphp bridge
      holding the given device, for this purpose.
      
      In addition to that, remove the dock station's list of
      "hotplug devices" and make the dock code always walk the whole list
      of "dependent devices" instead in such a way that the loops in
      hotplug_dock_devices() and dock_event() (replacing the loops over
      "hotplug devices") will take references to the list entries that
      register_hotplug_dock_device() has been called for.  That prevents
      the "release" routines associated with those entries from being
      called while the given entry is being processed and for PCI
      devices this means that their bridges won't be removed (by a
      concurrent thread) while hotplug_event_func() handling them is
      being executed.
      
      This change is based on two earlier patches from Jiang Liu.
      
      References: https://bugzilla.kernel.org/show_bug.cgi?id=59501Reported-and-tested-by: default avatarAlexander E. Patrakov <patrakov@gmail.com>
      Tracked-down-by: default avatarJiang Liu <jiang.liu@huawei.com>
      Tested-by: default avatarIllya Klymov <xanf@xanf.me>
      Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Acked-by: default avatarYinghai Lu <yinghai@kernel.org>
      Cc: 3.9+ <stable@vger.kernel.org>
      21a31013
  2. 22 Jun, 2013 1 commit
  3. 19 Jun, 2013 1 commit
    • Rafael J. Wysocki's avatar
      ACPI / dock: Take ACPI scan lock in write_undock() · 8112006f
      Rafael J. Wysocki authored
      Since commit 3757b948 (ACPI / hotplug: Fix concurrency issues and
      memory leaks) acpi_bus_scan() and acpi_bus_trim() must always be
      called under acpi_scan_lock, but currently the following scenario
      violating that requirement is possible:
      
       write_undock()
        handle_eject_request()
         hotplug_dock_devices()
          dock_remove_acpi_device()
           acpi_bus_trim()
      
      Fix that by making write_undock() acquire acpi_scan_lock before
      calling handle_eject_request() as appropriate (begin_undock() is
      under the lock too in analogy with acpi_dock_deferred_cb()).
      Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Cc: 3.9+ <stable@vger.kernel.org>
      Acked-by: default avatarToshi Kani <toshi.kani@hp.com>
      8112006f
  4. 13 Feb, 2013 1 commit
    • Rafael J. Wysocki's avatar
      ACPI / hotplug: Fix concurrency issues and memory leaks · 3757b948
      Rafael J. Wysocki authored
      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: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Acked-by: default avatarYinghai Lu <yinghai@kernel.org>
      3757b948
  5. 02 Feb, 2013 1 commit
  6. 25 Jan, 2013 1 commit
  7. 18 Jan, 2013 1 commit
    • Rafael J. Wysocki's avatar
      ACPI / scan: Drop acpi_bus_add() and use acpi_bus_scan() instead · b8bd759a
      Rafael J. Wysocki authored
      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: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Acked-by: default avatarYinghai Lu <yinghai@kernel.org>
      b8bd759a
  8. 15 Jan, 2013 1 commit
  9. 03 Jan, 2013 2 commits
    • Rafael J. Wysocki's avatar
      ACPI: Make acpi_bus_scan() and acpi_bus_add() take only one argument · 0cd6ac52
      Rafael J. Wysocki authored
      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: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Acked-by: default avatarYinghai Lu <yinghai@kernel.org>
      Acked-by: default avatarToshi Kani <toshi.kani@hp.com>
      0cd6ac52
    • Rafael J. Wysocki's avatar
      ACPI: Remove the arguments of acpi_bus_add() that are not used · 636458de
      Rafael J. Wysocki authored
      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: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Acked-by: default avatarYinghai Lu <yinghai@kernel.org>
      Acked-by: default avatarToshi Kani <toshi.kani@hp.com>
      636458de
  10. 21 Nov, 2012 1 commit
  11. 14 Nov, 2012 1 commit
  12. 12 Jan, 2012 1 commit
  13. 16 Jul, 2011 1 commit
  14. 12 Jan, 2011 1 commit
    • Lin Ming's avatar
      ACPICA: Rename some function and variable names · 3a37898d
      Lin Ming authored
      Some function and variable names are renamed to be consistent with
      ACPICA code base.
      
      acpi_raw_enable_gpe -> acpi_ev_add_gpe_reference
      acpi_raw_disable_gpe -> acpi_ev_remove_gpe_reference
      acpi_gpe_can_wake -> acpi_setup_gpe_for_wake
      acpi_gpe_wakeup -> acpi_set_gpe_wake_mask
      acpi_update_gpes -> acpi_update_all_gpes
      acpi_all_gpes_initialized -> acpi_gbl_all_gpes_initialized
      acpi_handler_info -> acpi_gpe_handler_info
      ...
      Signed-off-by: default avatarLin Ming <ming.m.lin@intel.com>
      Signed-off-by: default avatarLen Brown <len.brown@intel.com>
      3a37898d
  15. 19 Oct, 2010 1 commit
    • Uwe Kleine-König's avatar
      ACPI dock: move some functions to .init.text · d38a5edf
      Uwe Kleine-König authored
      find_dock and find_bay are only called by dock_init which lives in
      .init.text dock_add is only called by find_dock and find_bay.  So all
      three functions can be moved to .init.text, too.
      
      This fixes:
      
              WARNING: vmlinux.o(.text+0x2134b7): Section mismatch in reference from the function dock_add() to the function .init.text:platform_device_register_resndata()
              The function dock_add() references
              the function __init platform_device_register_resndata().
              This is often because dock_add lacks a __init
              annotation or the annotation of platform_device_register_resndata is wrong.
      
      for a build with unset CONFIG_MODULES.
      Signed-off-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
      Acked-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      Signed-off-by: default avatarLen Brown <len.brown@intel.com>
      d38a5edf
  16. 24 Sep, 2010 1 commit
    • Rafael J. Wysocki's avatar
      ACPI / ACPICA: Defer enabling of runtime GPEs (v3) · a2100801
      Rafael J. Wysocki authored
      The current ACPI GPEs initialization code has a problem that it
      enables some GPEs pointed to by device _PRW methods, generally
      intended for signaling wakeup events (system or device wakeup).
      These GPEs are then almost immediately disabled by the ACPI namespace
      scanning code with the help of acpi_gpe_can_wake(), but it would be
      better not to enable them at all until really necessary.
      
      Modify the initialization of GPEs so that the ones that have
      associated _Lxx or _Exx methods and are not pointed to by any _PRW
      methods will be enabled after the namespace scan is complete.
      Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
      Signed-off-by: default avatarLen Brown <len.brown@intel.com>
      a2100801
  17. 30 Mar, 2010 1 commit
    • Tejun Heo's avatar
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo authored
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Guess-its-ok-by: default avatarChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  18. 22 Mar, 2010 1 commit
  19. 16 Feb, 2010 1 commit
  20. 09 Feb, 2010 1 commit
  21. 16 Dec, 2009 5 commits
  22. 24 Nov, 2009 1 commit
  23. 03 Nov, 2009 1 commit
  24. 02 Oct, 2009 1 commit
  25. 28 Aug, 2009 1 commit
  26. 27 Aug, 2009 1 commit
    • Bob Moore's avatar
      ACPICA: Major update for acpi_get_object_info external interface · 15b8dd53
      Bob Moore authored
      Completed a major update for the acpi_get_object_info external interface.
      Changes include:
       - Support for variable, unlimited length HID, UID, and CID strings
       - Support Processor objects the same as Devices (HID,UID,CID,ADR,STA, etc.)
       - Call the _SxW power methods on behalf of a device object
       - Determine if a device is a PCI root bridge
       - Change the ACPI_BUFFER parameter to ACPI_DEVICE_INFO.
      These changes will require an update to all callers of this interface.
      See the ACPICA Programmer Reference for details.
      
      Also, update all invocations of acpi_get_object_info interface
      Signed-off-by: default avatarBob Moore <robert.moore@intel.com>
      Signed-off-by: default avatarLin Ming <ming.m.lin@intel.com>
      Signed-off-by: default avatarLen Brown <len.brown@intel.com>
      15b8dd53
  27. 03 Apr, 2009 1 commit
  28. 24 Mar, 2009 1 commit
    • Ming Lei's avatar
      Driver core: implement uevent suppress in kobject · f67f129e
      Ming Lei authored
      This patch implements uevent suppress in kobject and removes it
      from struct device, based on the following ideas:
      
      1,Uevent sending should be one attribute of kobject, so suppressing it
      in kobject layer is more natural than in device layer. By this way,
      we can do it for other objects embedded with kobject.
      
      2,It may save several bytes for each instance of struct device.(On my
      omap3(32bit ARM) based box, can save 8bytes per device object)
      
      This patch also introduces dev_set|get_uevent_suppress() helpers to
      set and query uevent_suppress attribute in case to help kobject
      as private part of struct device in future.
      
      [This version is against the latest driver-core patch set of Greg,please
      ignore the last version.]
      Signed-off-by: default avatarMing Lei <tom.leiming@gmail.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      f67f129e
  29. 06 Feb, 2009 2 commits
  30. 11 Oct, 2008 1 commit
  31. 10 Oct, 2008 1 commit
  32. 23 Sep, 2008 3 commits