linux-stable.git/drivers/acpi, branch v3.10 Linux kernel stable tree ACPI / dock / PCI: Synchronous handling of dock events for PCI devices 2013-06-24T09:22:53+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2013-06-24T09:22:53+00:00 21a31013f774c726bd199526cd673acc6432b21d 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=59501 Reported-and-tested-by: Alexander E. Patrakov <patrakov@gmail.com> Tracked-down-by: Jiang Liu <jiang.liu@huawei.com> Tested-by: Illya Klymov <xanf@xanf.me> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Cc: 3.9+ <stable@vger.kernel.org> 
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=59501
Reported-and-tested-by: Alexander E. Patrakov <patrakov@gmail.com>
Tracked-down-by: Jiang Liu <jiang.liu@huawei.com>
Tested-by: Illya Klymov <xanf@xanf.me>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: 3.9+ <stable@vger.kernel.org>
ACPI / dock: Initialize ACPI dock subsystem upfront 2013-06-22T22:59:55+00:00 Jiang Liu jiang.liu@huawei.com 2013-06-22T22:59:55+00:00 94add0f82469fa3c4ff978d03a34da90813c819d Commit 3b63aaa70e1 (PCI: acpiphp: Do not use ACPI PCI subdriver mechanism) introduced an ACPI dock support regression, because it changed the relative initialization order of the ACPI dock subsystem and the ACPI-based PCI hotplug (acpiphp). Namely, the ACPI dock subsystem has to be initialized before acpiphp_enumerate_slots() is first run, which after commit 3b63aaa70e1 happens during the initial enumeration of the PCI hierarchy triggered by the initial ACPI namespace scan in acpi_scan_init(). For this reason, the dock subsystem has to be initialized before the initial ACPI namespace scan in acpi_scan_init(). To make that happen, modify the ACPI dock subsystem to be non-modular and add the invocation of its initialization routine, acpi_dock_init(), to acpi_scan_init() directly before the initial namespace scan. [rjw: Changelog, removal of dock_exit().] References: https://bugzilla.kernel.org/show_bug.cgi?id=59501 Reported-and-tested-by: Alexander E. Patrakov <patrakov@gmail.com> Tested-by: Illya Klymov <xanf@xanf.me> Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Cc: 3.9+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Commit 3b63aaa70e1 (PCI: acpiphp: Do not use ACPI PCI subdriver
mechanism) introduced an ACPI dock support regression, because it
changed the relative initialization order of the ACPI dock subsystem
and the ACPI-based PCI hotplug (acpiphp).

Namely, the ACPI dock subsystem has to be initialized before
acpiphp_enumerate_slots() is first run, which after commit
3b63aaa70e1 happens during the initial enumeration of the PCI
hierarchy triggered by the initial ACPI namespace scan in
acpi_scan_init().  For this reason, the dock subsystem has to be
initialized before the initial ACPI namespace scan in
acpi_scan_init().

To make that happen, modify the ACPI dock subsystem to be
non-modular and add the invocation of its initialization routine,
acpi_dock_init(), to acpi_scan_init() directly before the initial
namespace scan.

[rjw: Changelog, removal of dock_exit().]
References: https://bugzilla.kernel.org/show_bug.cgi?id=59501
Reported-and-tested-by: Alexander E. Patrakov <patrakov@gmail.com>
Tested-by: Illya Klymov <xanf@xanf.me>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: 3.9+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / LPSS: Power up LPSS devices during enumeration 2013-06-19T22:49:06+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2013-06-18T22:45:34+00:00 b9e95fc65ededbec083aa91b4faa58ad992c0891 Commit 7cd8407 (ACPI / PM: Do not execute _PS0 for devices without _PSC during initialization) introduced a regression on some systems with Intel Lynxpoint Low-Power Subsystem (LPSS) where some devices need to be powered up during initialization, but their device objects in the ACPI namespace have _PS0 and _PS3 only (without _PSC or power resources). To work around this problem, make the ACPI LPSS driver power up devices it knows about by using a new helper function acpi_device_fix_up_power() that does all of the necessary sanity checks and calls acpi_dev_pm_explicit_set() to put the device into D0. Reported-and-tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Commit 7cd8407 (ACPI / PM: Do not execute _PS0 for devices without
_PSC during initialization) introduced a regression on some systems
with Intel Lynxpoint Low-Power Subsystem (LPSS) where some devices
need to be powered up during initialization, but their device objects
in the ACPI namespace have _PS0 and _PS3 only (without _PSC or power
resources).

To work around this problem, make the ACPI LPSS driver power up
devices it knows about by using a new helper function
acpi_device_fix_up_power() that does all of the necessary
sanity checks and calls acpi_dev_pm_explicit_set() to put the
device into D0.

Reported-and-tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / PM: Fix error code path for power resources initialization 2013-06-19T22:47:55+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2013-06-18T22:44:45+00:00 6ee22e9d59151550a55d370b14109bdae8b58bda Commit 781d737 (ACPI: Drop power resources driver) introduced a bug in the power resources initialization error code path causing a NULL pointer to be referenced in acpi_release_power_resource() if there's an error triggering a jump to the 'err' label in acpi_add_power_resource(). This happens because the list_node field of struct acpi_power_resource has not been initialized yet at this point and doing a list_del() on it is a bad idea. To prevent this problem from occuring, initialize the list_node field of struct acpi_power_resource upfront. Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: 3.9+ <stable@vger.kernel.org> Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> 
Commit 781d737 (ACPI: Drop power resources driver) introduced a
bug in the power resources initialization error code path causing
a NULL pointer to be referenced in acpi_release_power_resource()
if there's an error triggering a jump to the 'err' label in
acpi_add_power_resource().  This happens because the list_node
field of struct acpi_power_resource has not been initialized yet
at this point and doing a list_del() on it is a bad idea.

To prevent this problem from occuring, initialize the list_node
field of struct acpi_power_resource upfront.

Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.9+ <stable@vger.kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
ACPI / dock: Take ACPI scan lock in write_undock() 2013-06-19T21:56:30+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2013-06-15T22:38:30+00:00 8112006f41fd76ddf4988f8ddd904563db85613c Since commit 3757b94 (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: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: 3.9+ <stable@vger.kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com> 
Since commit 3757b94 (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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.9+ <stable@vger.kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
ACPI / resources: call acpi_get_override_irq() only for legacy IRQ resources 2013-06-19T21:55:59+00:00 Mika Westerberg mika.westerberg@linux.intel.com 2013-05-20T15:41:45+00:00 204ebc0aa30a7115f300cac39fbb7eeb66524881 acpi_get_override_irq() was added because there was a problem with buggy BIOSes passing wrong IRQ() resource for the RTC IRQ. The commit that added the workaround was 61fd47e0c8476 (ACPI: fix two IRQ8 issues in IOAPIC mode). With ACPI 5 enumerated devices there are typically one or more extended IRQ resources per device (and these IRQs can be shared). However, the acpi_get_override_irq() workaround forces all IRQs in range 0 - 15 (the legacy ISA IRQs) to be edge triggered, active high as can be seen from the dmesg below: ACPI: IRQ 6 override to edge, high ACPI: IRQ 7 override to edge, high ACPI: IRQ 7 override to edge, high ACPI: IRQ 13 override to edge, high Also /proc/interrupts for the I2C controllers (INT33C2 and INT33C3) shows the same thing: 7: 4 0 0 0 IO-APIC-edge INT33C2:00, INT33C3:00 The _CSR method for INT33C2 (and INT33C3) device returns following resource: Interrupt (ResourceConsumer, Level, ActiveLow, Shared,,, ) { 0x00000007, } which states that this is supposed to be level triggered, active low, shared IRQ instead. Fix this by making sure that acpi_get_override_irq() gets only called when we are dealing with legacy IRQ() or IRQNoFlags() descriptors. While we are there, correct pr_warning() to print the right triggering value. This change turns out to be necessary to make DMA work correctly on systems based on the Intel Lynxpoint PCH (Platform Controller Hub). [rjw: Changelog] Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: 3.9+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
acpi_get_override_irq() was added because there was a problem with
buggy BIOSes passing wrong IRQ() resource for the RTC IRQ.  The
commit that added the workaround was 61fd47e0c8476 (ACPI: fix two
IRQ8 issues in IOAPIC mode).

With ACPI 5 enumerated devices there are typically one or more
extended IRQ resources per device (and these IRQs can be shared).
However, the acpi_get_override_irq() workaround forces all IRQs in
range 0 - 15 (the legacy ISA IRQs) to be edge triggered, active high
as can be seen from the dmesg below:

	ACPI: IRQ 6 override to edge, high
	ACPI: IRQ 7 override to edge, high
	ACPI: IRQ 7 override to edge, high
	ACPI: IRQ 13 override to edge, high

Also /proc/interrupts for the I2C controllers (INT33C2 and INT33C3) shows
the same thing:

	7:          4          0          0          0   IO-APIC-edge INT33C2:00, INT33C3:00

The _CSR method for INT33C2 (and INT33C3) device returns following
resource:

	Interrupt (ResourceConsumer, Level, ActiveLow, Shared,,, )
	{
		0x00000007,
	}

which states that this is supposed to be level triggered, active low,
shared IRQ instead.

Fix this by making sure that acpi_get_override_irq() gets only called
when we are dealing with legacy IRQ() or IRQNoFlags() descriptors.

While we are there, correct pr_warning() to print the right triggering
value.

This change turns out to be necessary to make DMA work correctly on
systems based on the Intel Lynxpoint PCH (Platform Controller Hub).

[rjw: Changelog]
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: 3.9+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / video: Do not bind to device objects with a scan handler 2013-06-10T11:00:29+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2013-06-10T11:00:29+00:00 8c9b7a7b2fc2750af418ddc28e707c42e78aa0bf With the introduction of ACPI scan handlers, ACPI device objects with an ACPI scan handler attached to them must not be bound to by ACPI drivers any more. Unfortunately, however, the ACPI video driver attempts to do just that if there is a _ROM ACPI control method defined under a device object with an ACPI scan handler. Prevent that from happening by making the video driver's "add" routine check if the device object already has an ACPI scan handler attached to it and return an error code in that case. That is not sufficient, though, because acpi_bus_driver_init() would then clear the device object's driver_data that may be set by its scan handler, so for the fix to work acpi_bus_driver_init() has to be modified to leave driver_data as is on errors. References: https://bugzilla.kernel.org/show_bug.cgi?id=58091 Bisected-and-tested-by: Dmitry S. Demin <dmitryy.demin@gmail.com> Reported-and-tested-by: Jason Cassell <bluesloth600@gmail.com> Tracked-down-by: Aaron Lu <aaron.lu@intel.com> Cc: 3.9+ <stable@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Aaron Lu <aaron.lu@intel.com> 
With the introduction of ACPI scan handlers, ACPI device objects
with an ACPI scan handler attached to them must not be bound to
by ACPI drivers any more.  Unfortunately, however, the ACPI video
driver attempts to do just that if there is a _ROM ACPI control
method defined under a device object with an ACPI scan handler.

Prevent that from happening by making the video driver's "add"
routine check if the device object already has an ACPI scan handler
attached to it and return an error code in that case.

That is not sufficient, though, because acpi_bus_driver_init() would
then clear the device object's driver_data that may be set by its
scan handler, so for the fix to work acpi_bus_driver_init() has to be
modified to leave driver_data as is on errors.

References: https://bugzilla.kernel.org/show_bug.cgi?id=58091
Bisected-and-tested-by: Dmitry S. Demin <dmitryy.demin@gmail.com>
Reported-and-tested-by: Jason Cassell <bluesloth600@gmail.com>
Tracked-down-by: Aaron Lu <aaron.lu@intel.com>
Cc: 3.9+ <stable@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Revert "ACPI / scan: do not match drivers against objects having scan handlers" 2013-06-08T01:33:12+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2013-06-08T00:55:07+00:00 ea7f665612fcc73da6b7698f468cd5fc03a30d47 Commit 9f29ab11ddbf ("ACPI / scan: do not match drivers against objects having scan handlers") introduced a boot regression on Tony's ia64 HP rx2600. Tony says: "It panics with the message: Kernel panic - not syncing: Unable to find SBA IOMMU: Try a generic or DIG kernel [...] my problem comes from arch/ia64/hp/common/sba_iommu.c where the code in sba_init() says: acpi_bus_register_driver(&acpi_sba_ioc_driver); if (!ioc_list) { but because of this change we never managed to call ioc_init() so ioc_list doesn't get set up, and we die." Revert it to avoid this breakage and we'll fix the problem it attempted to address later. Reported-by: Tony Luck <tony.luck@gmail.com> Cc: 3.9+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Commit 9f29ab11ddbf ("ACPI / scan: do not match drivers against objects
having scan handlers") introduced a boot regression on Tony's ia64 HP
rx2600.  Tony says:

  "It panics with the message:

   Kernel panic - not syncing: Unable to find SBA IOMMU: Try a generic or DIG kernel

   [...] my problem comes from arch/ia64/hp/common/sba_iommu.c
   where the code in sba_init() says:

        acpi_bus_register_driver(&acpi_sba_ioc_driver);
        if (!ioc_list) {

   but because of this change we never managed to call ioc_init()
   so ioc_list doesn't get set up, and we die."

Revert it to avoid this breakage and we'll fix the problem it attempted
to address later.

Reported-by: Tony Luck <tony.luck@gmail.com>
Cc: 3.9+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'acpi-fixes' 2013-06-07T10:35:23+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2013-06-07T10:35:23+00:00 2314b69253a42f8814cd6e3830b8538b815f1c11 * acpi-fixes: ACPI / PM: Do not execute _PS0 for devices without _PSC during initialization ACPI / scan: do not match drivers against objects having scan handlers ACPI / APEI: fix error return code in ghes_probe() ACPI / video: ignore BIOS initial backlight value for HP Pavilion g6 ACPI / video: ignore BIOS initial backlight value for HP m4 x86 / platform / hp_wmi: Fix bluetooth_rfkill misuse in hp_wmi_rfkill_setup() 
* acpi-fixes:
  ACPI / PM: Do not execute _PS0 for devices without _PSC during initialization
  ACPI / scan: do not match drivers against objects having scan handlers
  ACPI / APEI: fix error return code in ghes_probe()
  ACPI / video: ignore BIOS initial backlight value for HP Pavilion g6
  ACPI / video: ignore BIOS initial backlight value for HP m4
  x86 / platform / hp_wmi: Fix bluetooth_rfkill misuse in hp_wmi_rfkill_setup()
ACPI / PM: Do not execute _PS0 for devices without _PSC during initialization 2013-06-07T10:33:57+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2013-06-05T12:01:19+00:00 7cd8407d53ef5fb0280fcbe34f42311472f90feb Commit b378549 (ACPI / PM: Do not power manage devices in unknown initial states) added code to force devices without _PSC, but having _PS0 defined in the ACPI namespace, into ACPI power state D0 by executing _PS0 for them. That turned out to break Toshiba P870-303, however, so revert that code. References: https://bugzilla.kernel.org/show_bug.cgi?id=58201 Reported-and-tested-by: Jerome Cantenot <jerome.cantenot@gmail.com> Tracked-down-by: Lan Tianyu <tianyu.lan@intel.com> Cc: 3.9+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Commit b378549 (ACPI / PM: Do not power manage devices in unknown
initial states) added code to force devices without _PSC, but having
_PS0 defined in the ACPI namespace, into ACPI power state D0 by
executing _PS0 for them.  That turned out to break Toshiba P870-303,
however, so revert that code.

References: https://bugzilla.kernel.org/show_bug.cgi?id=58201
Reported-and-tested-by: Jerome Cantenot <jerome.cantenot@gmail.com>
Tracked-down-by: Lan Tianyu <tianyu.lan@intel.com>
Cc: 3.9+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>