I originally submitted a patch to workaround this by pushing all Ejection
Requests and Device Checks onto the kacpi_hotplug queue.

http://marc.info/?l=linux-acpi&m=131678270930105&w=2

The patch is still insufficient in that Bus Checks also need to be added.

Rather than add all events, including non-PCI-hotplug events, to the
hotplug queue, mjg suggested that a better approach would be to modify
the acpiphp driver so only acpiphp events would be added to the
kacpi_hotplug queue.

It's a longer patch, but at least we maintain the benefit of having separate
queues in ACPI.  This, of course, is still only a workaround the problem.
As Bjorn and mjg pointed out, we have to refactor a lot of this code to do
the right thing but at this point it is a better to have this code working.

The acpi core places all events on the kacpi_notify queue.  When the acpiphp
driver is loaded and a PCI card with a PCI-to-PCI bridge is removed the
following call sequence occurs:

cleanup_p2p_bridge()
	    -> cleanup_bridge()
		    -> acpi_remove_notify_handler()
			    -> acpi_os_wait_events_complete()
				    -> flush_workqueue(kacpi_notify_wq)

which is the queue we are currently executing on and the process will hang.

Move all hotplug acpiphp events onto the kacpi_hotplug workqueue.  In
handle_hotplug_event_bridge() and handle_hotplug_event_func() we can simply
push the rest of the work onto the kacpi_hotplug queue and then avoid the
deadlock.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: mjg@redhat.com
Cc: bhelgaas@google.com
Cc: linux-acpi@vger.kernel.org
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

All ACPICA locks are allocated by the same function,
acpi_os_create_lock(), with the help of a local variable called
"lock".  Thus, when lockdep is enabled, it uses "lock" as the
name of all those locks and regards them as instances of the same
lock, which causes it to report possible locking problems with them
when there aren't any.

To work around this problem, define acpi_os_create_lock() as a macro
and make it pass its argument to spin_lock_init(), so that lockdep
uses it as the name of the new lock.  Define this macron in a
Linux-specific file, to minimize the resulting modifications of
the OS-independent ACPICA parts.

This change is based on an earlier patch from Andrea Righi and it
addresses a regression from 2.6.39 tracked as
https://bugzilla.kernel.org/show_bug.cgi?id=38152

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-and-tested-by: Borislav Petkov <bp@alien8.de>
Tested-by: Andrea Righi <andrea@betterlinux.com>
Reviewed-by: Florian Mickler <florian@mickler.org>
Signed-off-by: Len Brown <len.brown@intel.com>

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Found by running make namespacecheck on linux-next

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Len Brown <len.brown@intel.com>

This function is not OS-dependent and has been replaced by
acpi_hw_derive_pci_id, which is now in the ACPICA core code.  Local
implementations of acpi_os_derive_pci_id are no longer necessary and
are removed. ACPICA BZ 857.

http://www.acpica.org/bugzilla/show_bug.cgi?id=857

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Adds install/remove interfaces so that the host can dynamically
alter the global _OSI table. Also adds support for _OSI handlers.
Additional support: new debugger command (osi), and test support in
the acpiexec utility. Adds new file, utilities/utosi.c.
ACPICA bugzilla 836.

The Linux OSL _OSI code is also changed.
acpi_osi_setup can't call acpi_install/remove_interface because ACPICA
is not initialized yet at this early time.
So we just save the osi string in acpi_osi_setup and will handle it
later in a new function acpi_osi_setup_late.

http://www.acpica.org/bugzilla/show_bug.cgi?id=836

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com
Signed-off-by: Len Brown <len.brown@intel.com>

Prototype in acpiosxf.h had the output value pointer as a (u32 *).
Should be a (u64 *).

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Simple rename of some parameters to standardize them.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>