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  1. 18 5月, 2013 1 次提交
  3. 18 4月, 2013 2 次提交
  5. 17 4月, 2013 4 次提交
  7. 16 4月, 2013 3 次提交
  9. 13 4月, 2013 5 次提交
  11. 14 2月, 2013 2 次提交
  13. 13 2月, 2013 1 次提交
    • R
      ACPI / hotplug: Fix concurrency issues and memory leaks · 3757b948
      由 Rafael J. Wysocki 提交于 
      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>
      3757b948
  15. 03 2月, 2013 1 次提交
    • J
      PCI: acpiphp: Remove dead code for PCI host bridge hotplug · be6d2867
      由 Jiang Liu 提交于 
      Commit 668192b6 "PCI: acpiphp: Move host bridge hotplug
to pci_root.c" has moved PCI host bridge hotplug logic from acpiphp
to pci_root, but there is still PCI host bridge hotplug related
dead code left in acpiphp. So remove those dead code.

Now companion ACPI devices are always created before corresponding
PCI devices. And the ACPI event handle_hotplug_event_bridge() will be
installed only if it has associated PCI device. So remove dead code to
handle bridge hot-adding in function handle_hotplug_event_bridge().
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      be6d2867
  17. 02 2月, 2013 2 次提交
  19. 26 1月, 2013 9 次提交
  21. 19 1月, 2013 1 次提交
    • R
      ACPI / scan: Drop acpi_bus_add() and use acpi_bus_scan() instead · b8bd759a
      由 Rafael J. Wysocki 提交于 
      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>
      b8bd759a
  23. 15 1月, 2013 3 次提交
    • R
      ACPI / scan: Drop the second argument of acpi_bus_trim() · ae281795
      由 Rafael J. Wysocki 提交于 
      All callers of acpi_bus_trim() pass 1 (true) as the second argument
of it, so remove that argument entirely and change acpi_bus_trim()
to always behave as though it were 1.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NToshi Kani <toshi.kani@hp.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
      ae281795
    • B
      PCI: shpchp: Use per-slot workqueues to avoid deadlock · f652e7d2
      由 Bjorn Helgaas 提交于 
      When we have an SHPC-capable bridge with a second SHPC-capable bridge
below it, pushing the upstream bridge's attention button causes a
deadlock.

The deadlock happens because we use the shpchp_wq workqueue to run
shpchp_pushbutton_thread(), which uses shpchp_disable_slot() to remove
devices below the upstream bridge.  When we remove the downstream bridge,
we call shpc_remove(), the shpchp driver's .remove() method.  That calls
flush_workqueue(shpchp_wq), which deadlocks because the
shpchp_pushbutton_thread() work item is still running.

This patch avoids the deadlock by creating a workqueue for every slot
and removing the single shared workqueue.

Here's the call path that leads to the deadlock:

  shpchp_queue_pushbutton_work
    queue_work(shpchp_wq)		# shpchp_pushbutton_thread
    ...

  shpchp_pushbutton_thread
    shpchp_disable_slot
      remove_board
        shpchp_unconfigure_device
          pci_stop_and_remove_bus_device
            ...
              shpc_remove		# shpchp driver .remove method
                hpc_release_ctlr
                  cleanup_slots
                    flush_workqueue(shpchp_wq)

This change is based on code inspection, since we don't have hardware
with this topology.
Based-on-patch-by: NYijing Wang <wangyijing@huawei.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
      f652e7d2
    • B
      PCI: shpchp: Handle push button event asynchronously · d347e758
      由 Bjorn Helgaas 提交于 
      Use non-ordered workqueue for attention button events.

Attention button events on each slot can be handled asynchronously. So
we should use non-ordered workqueue. This patch also removes ordered
workqueue in shpchp as a result.

486b10b9 ("PCI: pciehp: Handle push button event asynchronously") made
the same change to pciehp.  I split this out from a patch by Yijing Wang
<wangyijing@huawei.com> so we fix one thing at a time and to make the
shpchp history correspond more closely with the pciehp history.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
      d347e758
  25. 14 1月, 2013 1 次提交
  27. 13 1月, 2013 1 次提交
    • Y
      PCI: pciehp: Use per-slot workqueues to avoid deadlock · c2be6f93
      由 Yijing Wang 提交于 
      When we have a hotplug-capable PCIe port with a second hotplug-capable
PCIe port below it, removing the device below the upstream port causes
a deadlock.

The deadlock happens because we use the pciehp_wq workqueue to run
pciehp_power_thread(), which uses pciehp_disable_slot() to remove devices
below the upstream port.  When we remove the downstream PCIe port, we call
pciehp_remove(), the pciehp driver's .remove() method.  That calls
flush_workqueue(pciehp_wq), which deadlocks because the
pciehp_power_thread() work item is still running.

This patch avoids the deadlock by creating a workqueue for every PCIe port
and removing the single shared workqueue.

Here's the call path that leads to the deadlock:

  pciehp_queue_pushbutton_work
    queue_work(pciehp_wq)                   # queue pciehp_power_thread
    ...

  pciehp_power_thread
    pciehp_disable_slot
      remove_board
	pciehp_unconfigure_device
	  pci_stop_and_remove_bus_device
	    ...
	      pciehp_remove                 # pciehp driver .remove method
		pciehp_release_ctrl
		  pcie_cleanup_slot
		    flush_workqueue(pciehp_wq)

This is fairly urgent because it can be caused by simply unplugging a
Thunderbolt adapter, as reported by Daniel below.

[bhelgaas: changelog]
Reference: http://lkml.kernel.org/r/CAMVG2ssiRgcTD1bej2tkUUfsWmpL5eNtPcNif9va2-Gzb2u8nQ@mail.gmail.comReported-and-tested-by: NDaniel J Blueman <daniel@quora.org>
Reviewed-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NYijing Wang <wangyijing@huawei.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
      c2be6f93
  29. 08 1月, 2013 1 次提交
  31. 03 1月, 2013 3 次提交
    • R
      ACPI: Make acpi_bus_scan() and acpi_bus_add() take only one argument · 0cd6ac52
      由 Rafael J. Wysocki 提交于 
      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>
      0cd6ac52
    • R
      ACPI: Remove the arguments of acpi_bus_add() that are not used · 636458de
      由 Rafael J. Wysocki 提交于 
      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>
      636458de
    • R
      ACPI: Remove acpi_start_single_object() and acpi_bus_start() · 02f57c67
      由 Rafael J. Wysocki 提交于 
      The ACPI PCI root bridge driver was the only ACPI driver implementing
the .start() callback, which isn't used by any ACPI drivers any more
now.

For this reason, acpi_start_single_object() has no purpose any more,
so remove it and all references to it.  Also remove
acpi_bus_start_device(), whose only purpose was to call
acpi_start_single_object().

Moreover, since after the removal of acpi_bus_start_device() the
only purpose of acpi_bus_start() remains to call
acpi_update_all_gpes(), move that into acpi_bus_add() and drop
acpi_bus_start() too, remove its header from acpi_bus.h and
update all of its former users accordingly.

This change was previously proposed in a different from by
Yinghai Lu.
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>
      02f57c67