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2019-07-12Merge tag 'driver-core-5.3-rc1' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core and debugfs updates from Greg KH: "Here is the "big" driver core and debugfs changes for 5.3-rc1 It's a lot of different patches, all across the tree due to some api changes and lots of debugfs cleanups. Other than the debugfs cleanups, in this set of changes we have: - bus iteration function cleanups - scripts/get_abi.pl tool to display and parse Documentation/ABI entries in a simple way - cleanups to Documenatation/ABI/ entries to make them parse easier due to typos and other minor things - default_attrs use for some ktype users - driver model documentation file conversions to .rst - compressed firmware file loading - deferred probe fixes All of these have been in linux-next for a while, with a bunch of merge issues that Stephen has been patient with me for" * tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits) debugfs: make error message a bit more verbose orangefs: fix build warning from debugfs cleanup patch ubifs: fix build warning after debugfs cleanup patch driver: core: Allow subsystems to continue deferring probe drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT arch_topology: Remove error messages on out-of-memory conditions lib: notifier-error-inject: no need to check return value of debugfs_create functions swiotlb: no need to check return value of debugfs_create functions ceph: no need to check return value of debugfs_create functions sunrpc: no need to check return value of debugfs_create functions ubifs: no need to check return value of debugfs_create functions orangefs: no need to check return value of debugfs_create functions nfsd: no need to check return value of debugfs_create functions lib: 842: no need to check return value of debugfs_create functions debugfs: provide pr_fmt() macro debugfs: log errors when something goes wrong drivers: s390/cio: Fix compilation warning about const qualifiers drivers: Add generic helper to match by of_node driver_find_device: Unify the match function with class_find_device() bus_find_device: Unify the match callback with class_find_device ...
2019-06-24drivers: Add generic helper to match by of_nodeSuzuki K Poulose1-0/+6
Add a helper to match device by the of_node. This will be later used to provide wrappers to the device iterators for {bus/class/driver}_find_device(). Convert other users to reuse this new helper. Cc: Alan Tull <atull@kernel.org> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: "David S. Miller" <davem@davemloft.net> Cc: devicetree@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Heiner Kallweit <hkallweit1@gmail.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Lee Jones <lee.jones@linaro.org> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: linux-fpga@vger.kernel.org Cc: linux-i2c@vger.kernel.org Cc: linux-spi@vger.kernel.org Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Mark Brown <broonie@kernel.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Maxime Ripard <maxime.ripard@bootlin.com> Cc: Moritz Fischer <mdf@kernel.org> Cc: Peter Rosin <peda@axentia.se> Cc: Rob Herring <robh+dt@kernel.org> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Thor Thayer <thor.thayer@linux.intel.com> Cc: Wolfram Sang <wsa@the-dreams.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-03driver core: Add helper device_find_child_by_name()Heikki Krogerus1-0/+28
It looks like the child device is often matched with a name. This introduces a helper that does it automatically. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Tested-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-04-25driver core: Clarify which counterparts to use to device_add()Borislav Petkov1-0/+5
It is not absolutely clear from the docs how the cleanup path after device_add() should look like so spell it out explicitly. No functional changes, just documentation. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-20driver core: Fix PM-runtime for links added during consumer probeRafael J. Wysocki1-2/+2
Commit 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance") introduced a regression that causes suppliers to be suspended prematurely for device links added during consumer driver probe if the initial PM-runtime status of the consumer is "suspended" and the consumer is resumed after adding the link and before pm_runtime_put_suppliers() is called. In that case, pm_runtime_put_suppliers() will drop the rpm_active refcount for the link by one and (since rpm_active is equal to two after the preceding consumer resume) the supplier's PM-runtime usage counter will be decremented, which may cause the supplier to suspend even though the consumer's PM-runtime status is "active". For this reason, partially revert commit 4c06c4e6cf63 as the problem it tried to fix needs to be addressed somewhat differently, and change pm_runtime_get_suppliers() and pm_runtime_put_suppliers() so that the latter only drops rpm_active references acquired by the former. [This requires adding a new field to struct device_link, but I coulnd't find a cleaner way to address the issue that would work in all cases.] This causes pm_runtime_put_suppliers() to effectively ignore device links added during consumer probe, so device_link_add() doesn't need to worry about ensuring that suppliers will remain active after pm_runtime_put_suppliers() for links created with DL_FLAG_RPM_ACTIVE set and it only needs to bump up rpm_active by one for those links, so pm_runtime_active_link() is not necessary any more. Fixes: 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance") Reported-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-13driver core: Fix possible supplier PM-usage counter imbalanceRafael J. Wysocki1-17/+4
If a stateless device link to a certain supplier with DL_FLAG_PM_RUNTIME set in the flags is added and then removed by the consumer driver's probe callback, the supplier's PM-runtime usage counter will be nonzero after that which effectively causes the supplier to remain "always on" going forward. Namely, device_link_add() called to add the link invokes device_link_rpm_prepare() which notices that the consumer driver is probing, so it increments the supplier's PM-runtime usage counter with the assumption that the link will stay around until pm_runtime_put_suppliers() is called by driver_probe_device(), but if the link goes away before that point, the supplier's PM-runtime usage counter will remain nonzero. To prevent that from happening, first rework pm_runtime_get_suppliers() and pm_runtime_put_suppliers() to use the rpm_active refounts of device links and make the latter only drop rpm_active and the supplier's PM-runtime usage counter for each link by one, unless rpm_active is one already for it. Next, modify device_link_add() to bump up the new link's rpm_active refcount and the suppliers PM-runtime usage counter by two, to prevent pm_runtime_put_suppliers(), if it is called subsequently, from suspending the supplier prematurely (in case its PM-runtime usage counter goes down to 0 in there). Due to the way rpm_put_suppliers() works, this change does not affect runtime suspend of the consumer ends of new device links (or, generally, device links for which DL_FLAG_PM_RUNTIME has just been set). Fixes: e2f3cd831a28 ("driver core: Fix handling of runtime PM flags in device_link_add()") Reported-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-01driver core: Add device link flag DL_FLAG_AUTOPROBE_CONSUMERRafael J. Wysocki1-1/+15
Add a new device link flag, DL_FLAG_AUTOPROBE_CONSUMER, to request the driver core to probe for a consumer driver automatically after binding a driver to the supplier device on a persistent managed device link. As unbinding the supplier driver on a managed device link causes the consumer driver to be detached from its device automatically, this flag provides a complementary mechanism which is needed to address some "composite device" use cases. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-01driver core: Make driver core own stateful device linksRafael J. Wysocki1-15/+54
Even though stateful device links are managed by the driver core in principle, their creators are allowed and sometimes even expected to drop references to them via device_link_del() or device_link_remove(), but that doesn't really play well with the "persistent" link concept. If "persistent" managed device links are created from driver probe callbacks, device_link_add() called to do that will take a new reference on the link each time the callback runs and those references will never be dropped, which kind of isn't nice. This issues arises because of the link reference counting carried out by device_link_add() for existing links, but that is only done to avoid deleting device links that may still be necessary, which shouldn't be a concern for managed (stateful) links. These device links are managed by the driver core and whoever creates one of them will need it at least as long as until the consumer driver is detached from its device and deleting it may be left to the driver core just fine. For this reason, rework device_link_add() to apply the reference counting to stateless links only and make device_link_del() and device_link_remove() drop references to stateless links only too. After this change, if called to add a stateful device link for a consumer-supplier pair for which a stateful device link is present already, device_link_add() will return the existing link without incrementing its reference counter. Accordingly, device_link_del() and device_link_remove() will WARN() and do nothing when called to drop a reference to a stateful link. Thus, effectively, all stateful device links will be owned by the driver core. In addition, clean up the handling of the link management flags, DL_FLAG_AUTOREMOVE_CONSUMER and DL_FLAG_AUTOREMOVE_SUPPLIER, so that (a) they are never set at the same time and (b) if device_link_add() is called for a consumer-supplier pair with an existing stateful link between them, the flags of that link will be combined with the flags passed to device_link_add() to ensure that the life time of the link is sufficient for all of the callers of device_link_add() for the same consumer-supplier pair. Update the device_link_add() kerneldoc comment to reflect the above changes. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-01driver core: Do not call rpm_put_suppliers() in pm_runtime_drop_link()Rafael J. Wysocki1-0/+3
Calling rpm_put_suppliers() from pm_runtime_drop_link() is excessive as it affects all suppliers of the consumer device and not just the one pointed to by the device link being dropped. Worst case it may cause the consumer device to stop working unexpectedly. Moreover, in principle it is racy with respect to runtime PM of the consumer device. To avoid these problems drop runtime PM references on the particular supplier pointed to by the link in question only and do that after the link has been dropped from the consumer device's list of links to suppliers, which is in device_link_free(). Fixes: a0504aecba76 ("PM / runtime: Drop usage count for suppliers at device link removal") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-01driver core: Fix adding device links to probing suppliersRafael J. Wysocki1-8/+66
Currently, it is not valid to add a device link from a consumer driver ->probe callback to a supplier that is still probing too, but generally this is a valid use case. For example, if the consumer has just acquired a resource that can only be available if the supplier is functional, adding a device link to that supplier right away should be safe (and even desirable arguably), but device_link_add() doesn't handle that case correctly and the initial state of the link created by it is wrong then. To address this problem, change the initial state of device links added between a probing supplier and a probing consumer to DL_STATE_CONSUMER_PROBE and update device_links_driver_bound() to skip such links on the supplier side. With this change, if the supplier probe completes first, device_links_driver_bound() called for it will skip the link state update and when it is called for the consumer, the link state will be updated to "active". In turn, if the consumer probe completes first, device_links_driver_bound() called for it will change the state of the link to "active" and when it is called for the supplier, the link status update will be skipped. However, in principle the supplier or consumer probe may still fail after the link has been added, so modify device_links_no_driver() to change device links in the "active" or "consumer probe" state to "dormant" on the supplier side and update __device_links_no_driver() to change the link state to "available" only if it is "consumer probe" or "active". Then, if the supplier probe fails first, the leftover link to the probing consumer will become "dormant" and device_links_no_driver() called for the consumer (when its probe fails) will clean it up. In turn, if the consumer probe fails first, it will either drop the link, or change its state to "available" and, in the latter case, when device_links_no_driver() is called for the supplier, it will update the link state to "dormant". [If the supplier probe fails, but the consumer probe succeeds, which should not happen as long as the consumer driver is correct, the link still will be around, but it will be "dormant" until the supplier is probed again.] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-01driver core: Fix handling of runtime PM flags in device_link_add()Rafael J. Wysocki1-15/+30
After commit ead18c23c263 ("driver core: Introduce device links reference counting"), if there is a link between the given supplier and the given consumer already, device_link_add() will refcount it and return it unconditionally without updating its flags. It is possible, however, that the second (or any subsequent) caller of device_link_add() for the same consumer-supplier pair will pass DL_FLAG_PM_RUNTIME, possibly along with DL_FLAG_RPM_ACTIVE, in flags to it and the existing link may not behave as expected then. First, if DL_FLAG_PM_RUNTIME is not set in the existing link's flags at all, it needs to be set like during the original initialization of the link. Second, if DL_FLAG_RPM_ACTIVE is passed to device_link_add() in flags (in addition to DL_FLAG_PM_RUNTIME), the existing link should to be updated to reflect the "active" runtime PM configuration of the consumer-supplier pair and extra care must be taken here to avoid possible destructive races with runtime PM of the consumer. To that end, redefine the rpm_active field in struct device_link as a refcount, initialize it to 1 and make rpm_resume() (for the consumer) and device_link_add() increment it whenever they acquire a runtime PM reference on the supplier device. Accordingly, make rpm_suspend() (for the consumer) and pm_runtime_clean_up_links() decrement it and drop runtime PM references to the supplier device in a loop until rpm_active becones 1 again. Fixes: ead18c23c263 ("driver core: Introduce device links reference counting") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-01driver core: Do not resume suppliers under device_links_write_lock()Rafael J. Wysocki1-6/+14
It is incorrect to call pm_runtime_get_sync() under device_links_write_lock(), because it may end up trying to take device_links_read_lock() while resuming the target device and that will deadlock in the non-SRCU case, so avoid that by resuming the supplier device in device_link_add() before calling device_links_write_lock(). Fixes: 21d5c57b3726 ("PM / runtime: Use device links") Fixes: baa8809f6097 ("PM / runtime: Optimize the use of device links") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-01driver core: Avoid careless re-use of existing device linksRafael J. Wysocki1-3/+20
After commit ead18c23c263 ("driver core: Introduce device links reference counting"), if there is a link between the given supplier and the given consumer already, device_link_add() will refcount it and return it unconditionally. However, if the flags passed to it on the second (or any subsequent) attempt to create a device link between the same consumer-supplier pair are not compatible with the existing link's flags, that is incorrect. First off, if the existing link is stateless and the next caller of device_link_add() for the same consumer-supplier pair wants a stateful one, or the other way around, the existing link cannot be returned, because it will not match the expected behavior, so make device_link_add() dump the stack and return NULL in that case. Moreover, if the DL_FLAG_AUTOREMOVE_CONSUMER flag is passed to device_link_add(), its caller will expect its reference to the link to be dropped automatically on consumer driver removal, which will not happen if that flag is not set in the link's flags (and analogously for DL_FLAG_AUTOREMOVE_SUPPLIER). For this reason, make device_link_add() update the existing link's flags accordingly before returning it to the caller. Fixes: ead18c23c263 ("driver core: Introduce device links reference counting") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-01driver core: Fix DL_FLAG_AUTOREMOVE_SUPPLIER device link flag handlingRafael J. Wysocki1-8/+12
Change the list walk in device_links_driver_cleanup() to a safe one to avoid use-after-free when dropping a link from the list during the walk. Also, while at it, fix device_link_add() to refuse to create stateless device links with DL_FLAG_AUTOREMOVE_SUPPLIER set, which is an invalid combination (setting that flag means that the driver core should manage the link, so it cannot be stateless), and extend the kerneldoc comment of device_link_add() to cover the DL_FLAG_AUTOREMOVE_SUPPLIER flag properly too. Fixes: 1689cac5b32a ("driver core: Add flag to autoremove device link on supplier unbind") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31driver core: Establish order of operations for device_add and device_del via ↵Alexander Duyck1-0/+11
bitflag Add an additional bit flag to the device_private struct named "dead". This additional flag provides a guarantee that when a device_del is executed on a given interface an async worker will not attempt to attach the driver following the earlier device_del call. Previously this guarantee was not present and could result in the device_del call attempting to remove a driver from an interface only to have the async worker attempt to probe the driver later when it finally completes the asynchronous probe call. One additional change added was that I pulled the check for dev->driver out of the __device_attach_driver call and instead placed it in the __device_attach_async_helper call. This was motivated by the fact that the only other caller of this, __device_attach, had already taken the device_lock() and checked for dev->driver. Instead of testing for this twice in this path it makes more sense to just consolidate the dev->dead and dev->driver checks together into one set of checks. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22driver core: Remove the link if there is no driver with AUTO flagYong Wu1-2/+2
DL_FLAG_AUTOREMOVE_CONSUMER/SUPPLIER means "Remove the link automatically on consumer/supplier driver unbind", that means we should remove whole the device_link when there is no this driver no matter what the ref_count of the link is. CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22driver core: silence device link messages unless debuggingJerome Brunet1-3/+3
On platforms making a fair use of regulators, the dev_info() messages coming from the device link function are a bit too verbose. The amount of message will increase further with the clock framework joining the device link party. These messages looks valuable for people debugging device link related issues, so dev_dbg() looks more appropriate than dev_info(). Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Acked-by: Kevin Hilman <khilman@baylibre.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-18driver core: move device->knode_class to device_privateWei Yang1-2/+2
As the description of struct device_private says, it stores data which is private to driver core. And it already has similar fields like: knode_parent, knode_driver, knode_driver and knode_bus. This look it is more proper to put knode_class together with those fields to make it private to driver core. This patch move device->knode_class to device_private to make it comply with code convention. Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-29Merge tag 'driver-core-4.21-rc1' of ↵Linus Torvalds1-10/+22
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the "big" set of driver core patches for 4.21-rc1. It's not really big, just a number of small changes for some reported issues, some documentation updates to hopefully make it harder for people to abuse the driver model, and some other minor cleanups. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: mm, memory_hotplug: update a comment in unregister_memory() component: convert to DEFINE_SHOW_ATTRIBUTE sysfs: Disable lockdep for driver bind/unbind files driver core: Add missing dev->bus->need_parent_lock checks kobject: return error code if writing /sys/.../uevent fails driver core: Move async_synchronize_full call driver core: platform: Respect return code of platform_device_register_full() kref/kobject: Improve documentation drivers/base/memory.c: Use DEVICE_ATTR_RO and friends driver core: Replace simple_strto{l,ul} by kstrtou{l,ul} kernfs: Improve kernfs_notify() poll notification latency kobject: Fix warnings in lib/kobject_uevent.c kobject: drop unnecessary cast "%llu" for u64 driver core: fix comments for device_block_probing() driver core: Replace simple_strtol by kstrtoint
2018-12-06kobject: return error code if writing /sys/.../uevent failsPeter Rajnoha1-1/+7
Propagate error code back to userspace if writing the /sys/.../uevent file fails. Before, the write operation always returned with success, even if we failed to recognize the input string or if we failed to generate the uevent itself. With the error codes properly propagated back to userspace, we are able to react in userspace accordingly by not assuming and awaiting a uevent that is not delivered. Signed-off-by: Peter Rajnoha <prajnoha@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-06kref/kobject: Improve documentationEzequiel Garcia1-2/+1
The current kref and kobject documentation may be insufficient to understand these common pitfalls regarding object lifetime and object releasing. Add a bit more documentation and improve the warnings seen by the user, pointing to the right piece of documentation. Also, it's important to understand that making fun of people publicly is not at all helpful, doesn't provide any value, and it's not a healthy way of encouraging developers to do better. "Mocking mercilessly" will, if anything, make developers feel bad and go away. This kind of behavior should not be encouraged or justified. Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> Signed-off-by: Matthias Brugger <mbrugger@suse.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Acked-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-27driver core: Replace simple_strto{l,ul} by kstrtou{l,ul}Kaitao cheng1-7/+14
The simple_strto{l,ul} are deprecated, use kstrtou{l,ul} instead. Signed-off-by: Kaitao cheng <pilgrimtao@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-26drivers: base: Introducing software nodes to the firmware node frameworkHeikki Krogerus1-0/+4
Software node is a new struct fwnode_handle type that can be used to describe devices in kernel (software). It is meant to complement fwnodes representing real firmware nodes when they are incomplete (for example missing device properties) and to supply the primary fwnode when the firmware lacks hardware description for a device completely. The software node type is really meant to replace the currently used "property_set" struct fwnode_handle type. The handling of struct property_set is glued to the generic device property handling code, and it is not possible to create a struct property_set independently from the device that it is bind to. struct property_set is only created when device properties are added to already initialized struct device, and control of it is only possible from the generic property handling code. Software nodes are instead designed to be created independently from the device entries (struct device). It makes them much more flexible, as then the device meant to be bind to the node can be created at a later time, and from another location. It is also possible to bind multiple devices to a single software node if needed. The software node implementation also includes support for node hierarchy, which was the main motivation for this commit. The node hierarchy was something that was requested for the struct property_set, but it did not seem reasonable to try to extend the property_set support for that purpose. struct property_set was really meant only for device property handling like the name suggests. Support for struct property_set is not yet removed in this commit, but it will be in the following one. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-11-26ACPI / glue: Add acpi_platform_notify() functionHeikki Krogerus1-0/+7
Instead of relying on the "platform_notify" callback hook, introducing separate notification function acpi_platform_notify() and calling that directly from drivers core when device entries are added and removed. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-11-26drivers core: Prepare support for multiple platform notificationsHeikki Krogerus1-7/+16
Since it should be possible to support several hardware description models at the same time (at least in theory), for example ACPI and devicetree on a running system, the platform notifications need to be handled differently. For now a single "platform_notify" callback function was used to notify the underlying base system which is in charge of the hardware description when a new device entry was added to the system, but that callback is available to only a single base system at the time. This will add a function device_platform_notify() and replace all direct platform_notify() calls with it. device_platform_notify() will first simply call the platform_notify() callback, so this commit has no functional affect, however, the idea is that individual base systems will put their direct notification calls there instead of using the platform_notify function pointer. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-08-18Merge tag 'driver-core-4.19-rc1' of ↵Linus Torvalds1-9/+14
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here are all of the driver core and related patches for 4.19-rc1. Nothing huge here, just a number of small cleanups and the ability to now stop the deferred probing after init happens. All of these have been in linux-next for a while with only a merge issue reported" * tag 'driver-core-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (21 commits) base: core: Remove WARN_ON from link dependencies check drivers/base: stop new probing during shutdown drivers: core: Remove glue dirs from sysfs earlier driver core: remove unnecessary function extern declare sysfs.h: fix non-kernel-doc comment PM / Domains: Stop deferring probe at the end of initcall iommu: Remove IOMMU_OF_DECLARE iommu: Stop deferring probe at end of initcalls pinctrl: Support stopping deferred probe after initcalls dt-bindings: pinctrl: add a 'pinctrl-use-default' property driver core: allow stopping deferred probe after init driver core: add a debugfs entry to show deferred devices sysfs: Fix internal_create_group() for named group updates base: fix order of OF initialization linux/device.h: fix kernel-doc notation warning Documentation: update firmware loader fallback reference kobject: Replace strncpy with memcpy drivers: base: cacheinfo: use OF property_read_u32 instead of get_property,read_number kernfs: Replace strncpy with memcpy device: Add #define dev_fmt similar to #define pr_fmt ...
2018-08-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-0/+9
Pull networking updates from David Miller: "Highlights: - Gustavo A. R. Silva keeps working on the implicit switch fallthru changes. - Support 802.11ax High-Efficiency wireless in cfg80211 et al, From Luca Coelho. - Re-enable ASPM in r8169, from Kai-Heng Feng. - Add virtual XFRM interfaces, which avoids all of the limitations of existing IPSEC tunnels. From Steffen Klassert. - Convert GRO over to use a hash table, so that when we have many flows active we don't traverse a long list during accumluation. - Many new self tests for routing, TC, tunnels, etc. Too many contributors to mention them all, but I'm really happy to keep seeing this stuff. - Hardware timestamping support for dpaa_eth/fsl-fman from Yangbo Lu. - Lots of cleanups and fixes in L2TP code from Guillaume Nault. - Add IPSEC offload support to netdevsim, from Shannon Nelson. - Add support for slotting with non-uniform distribution to netem packet scheduler, from Yousuk Seung. - Add UDP GSO support to mlx5e, from Boris Pismenny. - Support offloading of Team LAG in NFP, from John Hurley. - Allow to configure TX queue selection based upon RX queue, from Amritha Nambiar. - Support ethtool ring size configuration in aquantia, from Anton Mikaev. - Support DSCP and flowlabel per-transport in SCTP, from Xin Long. - Support list based batching and stack traversal of SKBs, this is very exciting work. From Edward Cree. - Busyloop optimizations in vhost_net, from Toshiaki Makita. - Introduce the ETF qdisc, which allows time based transmissions. IGB can offload this in hardware. From Vinicius Costa Gomes. - Add parameter support to devlink, from Moshe Shemesh. - Several multiplication and division optimizations for BPF JIT in nfp driver, from Jiong Wang. - Lots of prepatory work to make more of the packet scheduler layer lockless, when possible, from Vlad Buslov. - Add ACK filter and NAT awareness to sch_cake packet scheduler, from Toke Høiland-Jørgensen. - Support regions and region snapshots in devlink, from Alex Vesker. - Allow to attach XDP programs to both HW and SW at the same time on a given device, with initial support in nfp. From Jakub Kicinski. - Add TLS RX offload and support in mlx5, from Ilya Lesokhin. - Use PHYLIB in r8169 driver, from Heiner Kallweit. - All sorts of changes to support Spectrum 2 in mlxsw driver, from Ido Schimmel. - PTP support in mv88e6xxx DSA driver, from Andrew Lunn. - Make TCP_USER_TIMEOUT socket option more accurate, from Jon Maxwell. - Support for templates in packet scheduler classifier, from Jiri Pirko. - IPV6 support in RDS, from Ka-Cheong Poon. - Native tproxy support in nf_tables, from Máté Eckl. - Maintain IP fragment queue in an rbtree, but optimize properly for in-order frags. From Peter Oskolkov. - Improvde handling of ACKs on hole repairs, from Yuchung Cheng" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1996 commits) bpf: test: fix spelling mistake "REUSEEPORT" -> "REUSEPORT" hv/netvsc: Fix NULL dereference at single queue mode fallback net: filter: mark expected switch fall-through xen-netfront: fix warn message as irq device name has '/' cxgb4: Add new T5 PCI device ids 0x50af and 0x50b0 net: dsa: mv88e6xxx: missing unlock on error path rds: fix building with IPV6=m inet/connection_sock: prefer _THIS_IP_ to current_text_addr net: dsa: mv88e6xxx: bitwise vs logical bug net: sock_diag: Fix spectre v1 gadget in __sock_diag_cmd() ieee802154: hwsim: using right kind of iteration net: hns3: Add vlan filter setting by ethtool command -K net: hns3: Set tx ring' tc info when netdev is up net: hns3: Remove tx ring BD len register in hns3_enet net: hns3: Fix desc num set to default when setting channel net: hns3: Fix for phy link issue when using marvell phy driver net: hns3: Fix for information of phydev lost problem when down/up net: hns3: Fix for command format parsing error in hclge_is_all_function_id_zero net: hns3: Add support for serdes loopback selftest bnxt_en: take coredump_record structure off stack ...
2018-08-14Merge tag 'pm-4.19-rc1' of ↵Linus Torvalds1-7/+18
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These add a new framework for CPU idle time injection, to be used by all of the idle injection code in the kernel in the future, fix some issues and add a number of relatively small extensions in multiple places. Specifics: - Add a new framework for CPU idle time injection (Daniel Lezcano). - Add AVS support to the armada-37xx cpufreq driver (Gregory CLEMENT). - Add support for current CPU frequency reporting to the ACPI CPPC cpufreq driver (George Cherian). - Rework the cooling device registration in the imx6q/thermal driver (Bastian Stender). - Make the pcc-cpufreq driver refuse to work with dynamic scaling governors on systems with many CPUs to avoid scalability issues with it (Rafael Wysocki). - Fix the intel_pstate driver to report different maximum CPU frequencies on systems where they really are different and to ignore the turbo active ratio if hardware-managend P-states (HWP) are in use; make it use the match_string() helper (Xie Yisheng, Srinivas Pandruvada). - Fix a minor deferred probe issue in the qcom-kryo cpufreq driver (Niklas Cassel). - Add a tracepoint for the tracking of frequency limits changes (from Andriod) to the cpufreq core (Ruchi Kandoi). - Fix a circular lock dependency between CPU hotplug and sysfs locking in the cpufreq core reported by lockdep (Waiman Long). - Avoid excessive error reports on driver registration failures in the ARM cpuidle driver (Sudeep Holla). - Add a new device links flag to the driver core to make links go away automatically on supplier driver removal (Vivek Gautam). - Eliminate potential race condition between system-wide power management transitions and system shutdown (Pingfan Liu). - Add a quirk to save NVS memory on system suspend for the ASUS 1025C laptop (Willy Tarreau). - Make more systems use suspend-to-idle (instead of ACPI S3) by default (Tristian Celestin). - Get rid of stack VLA usage in the low-level hibernation code on 64-bit x86 (Kees Cook). - Fix error handling in the hibernation core and mark an expected fall-through switch in it (Chengguang Xu, Gustavo Silva). - Extend the generic power domains (genpd) framework to support attaching a device to a power domain by name (Ulf Hansson). - Fix device reference counting and user limits initialization in the devfreq core (Arvind Yadav, Matthias Kaehlcke). - Fix a few issues in the rk3399_dmc devfreq driver and improve its documentation (Enric Balletbo i Serra, Lin Huang, Nick Milner). - Drop a redundant error message from the exynos-ppmu devfreq driver (Markus Elfring)" * tag 'pm-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (35 commits) PM / reboot: Eliminate race between reboot and suspend PM / hibernate: Mark expected switch fall-through cpufreq: intel_pstate: Ignore turbo active ratio in HWP cpufreq: Fix a circular lock dependency problem cpu/hotplug: Add a cpus_read_trylock() function x86/power/hibernate_64: Remove VLA usage cpufreq: trace frequency limits change cpufreq: intel_pstate: Show different max frequency with turbo 3 and HWP cpufreq: pcc-cpufreq: Disable dynamic scaling on many-CPU systems cpufreq: qcom-kryo: Silently error out on EPROBE_DEFER cpufreq / CPPC: Add cpuinfo_cur_freq support for CPPC cpufreq: armada-37xx: Add AVS support dt-bindings: marvell: Add documentation for the Armada 3700 AVS binding PM / devfreq: rk3399_dmc: Fix duplicated opp table on reload. PM / devfreq: Init user limits from OPP limits, not viceversa PM / devfreq: rk3399_dmc: fix spelling mistakes. PM / devfreq: rk3399_dmc: do not print error when get supply and clk defer. dt-bindings: devfreq: rk3399_dmc: move interrupts to be optional. PM / devfreq: rk3399_dmc: remove wait for dcf irq event. dt-bindings: clock: add rk3399 DDR3 standard speed bins. ...
2018-08-10Merge branch 'regulator-4.19' into regulator-nextMark Brown1-0/+30
2018-07-21base: core: Remove WARN_ON from link dependencies checkBenjamin Gaignard1-2/+2
In some cases the link between between customer and supplier already exist, for example when a device use its parent as a supplier. Do not warn about already existing dependencies because device_link_add() takes care of this case. Link: http://lkml.kernel.org/r/20180709111753eucas1p1f32e66fb2f7ea3216097cd72a132355d~-rzycA5Rg0378203782eucas1p1C@eucas1p1.samsung.com Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Reviewed-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-21drivers/base: stop new probing during shutdownPingfan Liu1-0/+3
There is a race window in device_shutdown(), which may cause -1. parent device shut down before child or -2. no shutdown on a new probing device. For 1st, taking the following scenario: device_shutdown new plugin device list_del_init(parent_dev); spin_unlock(list_lock); device_add(child) probe child shutdown parent_dev --> now child is on the tail of devices_kset For 2nd, taking the following scenario: device_shutdown new plugin device device_add(dev) device_lock(dev); ... device_unlock(dev); probe dev --> now, the new occurred dev has no opportunity to shutdown To fix this race issue, just prevent the new probing request. With this logic, device_shutdown() is more similar to dpm_prepare(). Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Reviewed-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-21driver core: set up ownership of class devices in sysfsDmitry Torokhov1-0/+9
Plumb in get_ownership() callback for devices belonging to a class so that they can be created with uid/gid different from global root. This will allow network devices in a container to belong to container's root and not global root. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-16drivers: core: Remove glue dirs from sysfs earlierBenjamin Herrenschmidt1-0/+2
For devices with a class, we create a "glue" directory between the parent device and the new device with the class name. This directory is never "explicitely" removed when empty however, this is left to the implicit sysfs removal done by kobject_release() when the object loses its last reference via kobject_put(). This is problematic because as long as it's not been removed from sysfs, it is still present in the class kset and in sysfs directory structure. The presence in the class kset exposes a use after free bug fixed by the previous patch, but the presence in sysfs means that until the kobject is released, which can take a while (especially with kobject debugging), any attempt at re-creating such as binding a new device for that class/parent pair, will result in a sysfs duplicate file name error. This fixes it by instead doing an explicit kobject_del() when the glue dir is empty, by keeping track of the number of child devices of the gluedir. This is made easy by the fact that all glue dir operations are done with a global mutex, and there's already a function (cleanup_glue_dir) called in all the right places taking that mutex that can be enhanced for this. It appears that this was in fact the intent of the function, but the implementation was wrong. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-16driver core: remove unnecessary function extern declareShaokun Zhang1-1/+1
device_private_init is called only in core.c, extern declare is unnecessary and make it static. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-09driver core: Add flag to autoremove device link on supplier unbindVivek Gautam1-0/+10
Add a flag to autoremove the device links on supplier driver unbind. This obviates the need to explicitly delete the link in the remove path. We remove these links only when the supplier's link to its consumers has gone to DL_STATE_SUPPLIER_UNBIND state. Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> Suggested-by: Lukas Wunner <lukas@wunner.de> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-07-09driver core: Rename flag AUTOREMOVE to AUTOREMOVE_CONSUMERVivek Gautam1-7/+8
Now that we want to add another flag to autoremove the device link on supplier unbind, it's fair to rename the existing flag from DL_FLAG_AUTOREMOVE to DL_FLAG_AUTOREMOVE_CONSUMER so that we can add similar flag for supplier later. And, while we are touching device.h, fix a doc build warning. Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-07-06device: Add #define dev_fmt similar to #define pr_fmtJoe Perches1-6/+6
Add a prefixing macro to dev_<level> uses similar to the pr_fmt prefixing macro used in pr_<level> calls. This can help avoid some string duplication in dev_<level> uses. The default, like pr_fmt, is an empty #define dev_fmt(fmt) fmt Rename the existing dev_<level> functions to _dev_<level> and introduce #define dev_<level> _dev_<level> macros that use the new #define dev_fmt Miscellanea: o Consistently use #defines with fmt, ... and ##__VA_ARGS__ o Remove unnecessary externs Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-05driver core: Add device_link_remove functionpascal paillet1-0/+30
Device_link_remove uses the same arguments than device_link_add. The Goal is to avoid storing the link pointer. Signed-off-by: pascal paillet <p.paillet@st.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-06-14PM / core: Fix supplier device runtime PM usage counter imbalanceRafael J. Wysocki1-4/+11
If a device link is added via device_link_add() by the driver of the link's consumer device, the supplier's runtime PM usage counter is going to be dropped by the pm_runtime_put_suppliers() call in driver_probe_device(). However, in that case it is not incremented unless the supplier driver is already present and the link is not stateless. That leads to a runtime PM usage counter imbalance for the supplier device in a few cases. To prevent that from happening, bump up the supplier runtime PM usage counter in device_link_add() for all links with the DL_FLAG_PM_RUNTIME flag set that are added at the consumer probe time. Use pm_runtime_get_noresume() for that as the callers of device_link_add() who want the supplier to be resumed by it are expected to pass DL_FLAG_RPM_ACTIVE in flags to it anyway, but additionally resume the supplier if the link is added during consumer driver probe to retain the existing behavior for the callers depending on it. Fixes: 21d5c57b3726 (PM / runtime: Use device links) Reported-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: 4.10+ <stable@vger.kernel.org> # 4.10+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-06Merge tag 'driver-core-4.18-rc1' of ↵Linus Torvalds1-4/+14
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the driver core patchset for 4.18-rc1. The large chunk of these are firmware core documentation and api updates. Nothing major there, just better descriptions for others to be able to understand the firmware code better. There's also a user for a new firmware api call. Other than that, there are some minor updates for debugfs, kernfs, and the driver core itself. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits) driver core: hold dev's parent lock when needed driver-core: return EINVAL error instead of BUG_ON() driver core: add __printf verification to device_create_groups_vargs mm: memory_hotplug: use put_device() if device_register fail base: core: fix typo 'can by' to 'can be' debugfs: inode: debugfs_create_dir uses mode permission from parent debugfs: Re-use kstrtobool_from_user() Documentation: clarify firmware_class provenance and why we can't rename the module Documentation: remove stale firmware API reference Documentation: fix few typos and clarifications for the firmware loader ath10k: re-enable the firmware fallback mechanism for testmode ath10k: use firmware_request_nowarn() to load firmware firmware: add firmware_request_nowarn() - load firmware without warnings firmware_loader: make firmware_fallback_sysfs() print more useful firmware_loader: move kconfig FW_LOADER entries to its own file firmware_loader: replace ---help--- with help firmware_loader: enhance Kconfig documentation over FW_LOADER firmware_loader: document firmware_sysfs_fallback() firmware: rename fw_sysfs_fallback to firmware_fallback_sysfs() firmware: use () to terminate kernel-doc function names ...
2018-05-14driver core: add __printf verification to device_create_groups_vargsMathieu Malaterre1-1/+1
__printf is useful to verify format and arguments. Remove the following warning (with W=1): drivers/base/core.c:2435:2: warning: function might be possible candidate for ‘gnu_printf’ format attribute [-Wsuggest-attribute=format] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14base: core: fix typo 'can by' to 'can be'Wolfram Sang1-1/+1
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14driver core: Don't ignore class_dir_create_and_add() failure.Tetsuo Handa1-2/+12
syzbot is hitting WARN() at kernfs_add_one() [1]. This is because kernfs_create_link() is confused by previous device_add() call which continued without setting dev->kobj.parent field when get_device_parent() failed by memory allocation fault injection. Fix this by propagating the error from class_dir_create_and_add() to the calllers of get_device_parent(). [1] https://syzkaller.appspot.com/bug?id=fae0fb607989ea744526d1c082a5b8de6529116f Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: syzbot <syzbot+df47f81c226b31d89fb1@syzkaller.appspotmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-24PM / core: fix deferred probe breaking suspend resume orderFeng Kan1-0/+20
When bridge and its endpoint is enumerated the devices are added to the dpm list. Afterward, the bridge defers probe when IOMMU is not ready. This causes the bridge to be moved to the end of the dpm list when deferred probe kicks in. The order of the dpm list for bridge and endpoint is reversed. Add reordering code to move the bridge and its children and consumers to the end of the pm list so the order for suspend and resume is not altered. The code also move device and its children and consumers to the tail of device_kset list if it is registered. Signed-off-by: Toan Le <toanle@apm.com> Signed-off-by: Feng Kan <fkan@apm.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-02-27driver core: Introduce device links reference countingLukas Wunner1-8/+17
If device_link_add() is invoked multiple times with the same supplier and consumer combo, it will create the link on first addition and return a pointer to the already existing link on all subsequent additions. The semantics for device_link_del() are quite different, it deletes the link unconditionally, so multiple invocations are not allowed. In other words, this snippet ... struct device *dev1, *dev2; struct device_link *link1, *link2; link1 = device_link_add(dev1, dev2, 0); link2 = device_link_add(dev1, dev2, 0); device_link_del(link1); device_link_del(link2); ... causes the following crash: WARNING: CPU: 4 PID: 2686 at drivers/base/power/runtime.c:1611 pm_runtime_drop_link+0x40/0x50 [...] list_del corruption, 0000000039b800a4->prev is LIST_POISON2 (00000000ecf79852) kernel BUG at lib/list_debug.c:50! The issue isn't as arbitrary as it may seem: Imagine a device link which is added in both the supplier's and the consumer's ->probe hook. The two drivers can't just call device_link_del() in their ->remove hook without coordination. Fix by counting multiple additions and dropping the device link only when the last addition is unwound. Signed-off-by: Lukas Wunner <lukas@wunner.de> [ rjw: Subject ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-02-12PM / runtime: Update links_count also if !CONFIG_SRCULukas Wunner1-0/+3
Commit baa8809f6097 (PM / runtime: Optimize the use of device links) added an invocation of pm_runtime_drop_link() to __device_link_del(). However there are two variants of that function, one for CONFIG_SRCU and another for !CONFIG_SRCU, and the commit only modified the former. Fixes: baa8809f6097 (PM / runtime: Optimize the use of device links) Cc: v4.10+ <stable@vger.kernel.org> # v4.10+ Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-02-02Merge branch 'for-linus' of ↵Linus Torvalds1-3/+2
git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk Pull printk updates from Petr Mladek: - Add a console_msg_format command line option: The value "default" keeps the old "[time stamp] text\n" format. The value "syslog" allows to see the syslog-like "<log level>[timestamp] text" format. This feature was requested by people doing regression tests, for example, 0day robot. They want to have both filtered and full logs at hands. - Reduce the risk of softlockup: Pass the console owner in a busy loop. This is a new approach to the old problem. It was first proposed by Steven Rostedt on Kernel Summit 2017. It marks a context in which the console_lock owner calls console drivers and could not sleep. On the other side, printk() callers could detect this state and use a busy wait instead of a simple console_trylock(). Finally, the console_lock owner checks if there is a busy waiter at the end of the special context and eventually passes the console_lock to the waiter. The hand-off works surprisingly well and helps in many situations. Well, there is still a possibility of the softlockup, for example, when the flood of messages stops and the last owner still has too much to flush. There is increasing number of people having problems with printk-related softlockups. We might eventually need to get better solution. Anyway, this looks like a good start and promising direction. - Do not allow to schedule in console_unlock() called from printk(): This reverts an older controversial commit. The reschedule helped to avoid softlockups. But it also slowed down the console output. This patch is obsoleted by the new console waiter logic described above. In fact, the reschedule made the hand-off less effective. - Deprecate "%pf" and "%pF" format specifier: It was needed on ia64, ppc64 and parisc64 to dereference function descriptors and show the real function address. It is done transparently by "%ps" and "pS" format specifier now. Sergey Senozhatsky found that all the function descriptors were in a special elf section and could be easily detected. - Remove printk_symbol() API: It has been obsoleted by "%pS" format specifier, and this change helped to remove few continuous lines and a less intuitive old API. - Remove redundant memsets: Sergey removed unnecessary memset when processing printk.devkmsg command line option. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (27 commits) printk: drop redundant devkmsg_log_str memsets printk: Never set console_may_schedule in console_trylock() printk: Hide console waiter logic into helpers printk: Add console owner and waiter logic to load balance console writes kallsyms: remove print_symbol() function checkpatch: add pF/pf deprecation warning symbol lookup: introduce dereference_symbol_descriptor() parisc64: Add .opd based function descriptor dereference powerpc64: Add .opd based function descriptor dereference ia64: Add .opd based function descriptor dereference sections: split dereference_function_descriptor() openrisc: Fix conflicting types for _exext and _stext lib: do not use print_symbol() irq debug: do not use print_symbol() sysfs: do not use print_symbol() drivers: do not use print_symbol() x86: do not use print_symbol() unicore32: do not use print_symbol() sh: do not use print_symbol() mn10300: do not use print_symbol() ...
2018-01-05drivers: do not use print_symbol()Sergey Senozhatsky1-3/+2
print_symbol() is a very old API that has been obsoleted by %pS format specifier in a normal printk() call. Replace print_symbol() with a direct printk("%pS") call. Link: http://lkml.kernel.org/r/20171211125025.2270-10-sergey.senozhatsky@gmail.com To: Andrew Morton <akpm@linux-foundation.org> To: Russell King <linux@armlinux.org.uk> To: Catalin Marinas <catalin.marinas@arm.com> To: Mark Salter <msalter@redhat.com> To: Tony Luck <tony.luck@intel.com> To: David Howells <dhowells@redhat.com> To: Yoshinori Sato <ysato@users.sourceforge.jp> To: Guan Xuetao <gxt@mprc.pku.edu.cn> To: Borislav Petkov <bp@alien8.de> To: Greg Kroah-Hartman <gregkh@linuxfoundation.org> To: Thomas Gleixner <tglx@linutronix.de> To: Peter Zijlstra <peterz@infradead.org> To: Vineet Gupta <vgupta@synopsys.com> To: Fengguang Wu <fengguang.wu@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Petr Mladek <pmladek@suse.com> Cc: LKML <linux-kernel@vger.kernel.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: linux-ia64@vger.kernel.org Cc: linux-am33-list@redhat.com Cc: linux-sh@vger.kernel.org Cc: linux-edac@vger.kernel.org Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> [pmladek@suse.com: updated commit message] Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-12-18drivers: base: omit redundant interationsGimcuan Hui1-1/+1
When error happens, these interators return the error, no interation should be continued, so make the change for getting out of while immediately. Signed-off-by: Gimcuan Hui <gimcuan@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-07driver core: Remove redundant license textGreg Kroah-Hartman1-3/+0
Now that the SPDX tag is in all driver core files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Johannes Berg <johannes@sipsolutions.net> Cc: "Luis R. Rodriguez" <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>