Fix to return -ENODEV in the acpi notify handler install error
handling case instead of 0, as done elsewhere in this function.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The local variable id in dock_add() is not necessary, so drop it.
While we're at it, use an initializer to clear the local variable ds
and drop the memset() used for this purpose.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The only user of the ACPI dock notifier chain is the ACPI-based PCI
hotplug (acpiphp) driver that uses it to carry out post-dock fixups
needed by some systems with broken _DCK. However, it is not
necessary to use a separate notifier chain for that, as it can be
simply replaced with a new callback in struct acpi_dock_ops.
For this reason, add a new .fixup() callback to struct acpi_dock_ops
and make hotplug_dock_devices() execute it for all dock devices with
hotplug operations registered. Accordingly, make acpiphp point that
callback to the function carrying out the post-dock fixups and
do not register a separate dock notifier for each device
registering dock operations. Finally, drop the ACPI dock notifier
chain that has no more users.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The function creating and registering dock station objects,
dock_add(), leaks memory if there's an error after it's walked
the ACPI namespace calling find_dock_devices(), because it doesn't
free the list of dependent devices it's just created in those cases.
Fix that issue by adding the missing code to free the list of
dependent devices on errors.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI dock driver uses register_acpi_bus_notifier() which
installs a notifier triggered globally for all system notifications.
That first of all is inefficient, because the dock driver is only
interested in notifications associated with the devices it handles,
but it has to handle all system notifies for all devices. Moreover,
it does that even if no docking stations are present in the system
(CONFIG_ACPI_DOCK set is sufficient for that to happen). Besides,
that is inconvenient, because it requires the driver to do extra work
for each notification to find the target dock station object.
For these reasons, rework the dock driver to install a notify
handler individually for each dock station in the system using
acpi_install_notify_handler(). This allows the dock station
object to be passed directly to the notify handler and makes it
possible to simplify the dock driver quite a bit. It also
reduces the overhead related to the handling of all system
notifies when CONFIG_ACPI_DOCK is set.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Make dock_init_hotplug() and dock_release_hotplug() slightly simpler
and move some checks in those functions to the code paths where they
are needed.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
If there are indirect dependencies between devices in a dock
station's dependent devices list, they may be broken if the devices
are removed in the same order in which they have been added.
For this reason, make the code in handle_eject_request() walk the
list of dependent devices in reverse order.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Since acpi_walk_namespace() calls find_dock_devices() during tree
pre-order visit, the latter doesn't need to add devices whose
parents have _EJD pointing to the docking station to the list of
that station's dependent devices, because those parents are going to
be added to that list anyway and the removal of a parent will take
care of the removal of its children in those cases.
For this reason, rework find_dock_devices() to only call
add_dock_dependent_device() for devices whose _EJD point directy to
the docking station represented by its context argument and simplify
it slightly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
The only existing user of the hp_lock mutex in struct dock_station,
hotplug_dock_devices(), is always called under acpi_scan_lock and
cannot race with another instance of itself, so drop the mutex
which is not necessary.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use helper functions introduced previously to simplify the ACPI dock
driver.
[rjw: Changelog]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The return value of dock_create_acpi_device() is not used at all,
so change its signature to return void and simplify the
implementation of it.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Mark all initialization functions with __init to reduce runtime
memory consumption.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
All dock station objects are created during initialization and
don't change at runtime, so drop the redundant spin lock from
struct dock_station.
[rjw: Changelog]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Function dock_add() will be called multiple times if there are
multiple dock stations, which causes acpi_dock_notifier_list to be
initialized multiple times.
To avoid that, move the initialization of acpi_dock_notifier_list
from dock_add() to acpi_dock_init().
[rjw: Changelog]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 94add0f (ACPI / dock: Initialize ACPI dock subsystem upfront)
changed the header of acpi_dock_init() in internal.h so that it is
supposed to be a void function now, but it forgot to update its
actual definition in dock.c according to which it still is supposed
to return int.
Although that didn't cause any visible breakage or even a compiler
warning to be thrown, which is odd enough, fix it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.10+ <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>
Commit 3b63aaa70e (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
3b63aaa70e 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>
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>
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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
acpi_bus_get_device() returns int not acpi_status.
The patch change not to apply ACPI_SUCCESS() to the return value of
acpi_bus_get_device().
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Rafael J. Wysocki
Hanjun Guo
Wei Yongjun
Jiang Liu
Yasuaki Ishimatsu