user/sven/linux.git/include/linux/device.h, branch v6.1.94

driver core: Introduce device_link_wait_removal()

2024-04-10T14:28:32Z

commit 0462c56c290a99a7f03e817ae5b843116dfb575c upstream. The commit 80dd33cf72d1 ("drivers: base: Fix device link removal") introduces a workqueue to release the consumer and supplier devices used in the devlink. In the job queued, devices are release and in turn, when all the references to these devices are dropped, the release function of the device itself is called. Nothing is present to provide some synchronisation with this workqueue in order to ensure that all ongoing releasing operations are done and so, some other operations can be started safely. For instance, in the following sequence: 1) of_platform_depopulate() 2) of_overlay_remove() During the step 1, devices are released and related devlinks are removed (jobs pushed in the workqueue). During the step 2, OF nodes are destroyed but, without any synchronisation with devlink removal jobs, of_overlay_remove() can raise warnings related to missing of_node_put(): ERROR: memory leak, expected refcount 1 instead of 2 Indeed, the missing of_node_put() call is going to be done, too late, from the workqueue job execution. Introduce device_link_wait_removal() to offer a way to synchronize operations waiting for the end of devlink removals (i.e. end of workqueue jobs). Also, as a flushing operation is done on the workqueue, the workqueue used is moved from a system-wide workqueue to a local one. Cc: stable@vger.kernel.org Signed-off-by: Herve Codina Tested-by: Luca Ceresoli Reviewed-by: Nuno Sa Reviewed-by: Saravana Kannan Acked-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20240325152140.198219-2-herve.codina@bootlin.com Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

locking: Introduce __cleanup() based infrastructure

2024-02-23T08:12:51Z

commit 54da6a0924311c7cf5015533991e44fb8eb12773 upstream. Use __attribute__((__cleanup__(func))) to build: - simple auto-release pointers using __free() - 'classes' with constructor and destructor semantics for scope-based resource management. - lock guards based on the above classes. Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20230612093537.614161713%40infradead.org Signed-off-by: Greg Kroah-Hartman

driver core: fw_devlink: Add DL_FLAG_CYCLE support to device links

2023-03-10T08:33:37Z

[ Upstream commit 67cad5c67019c38126b749621665b6723d3ae7e6 ] fw_devlink uses DL_FLAG_SYNC_STATE_ONLY device link flag for two purposes: 1. To allow a parent device to proxy its child device's dependency on a supplier so that the supplier doesn't get its sync_state() callback before the child device/consumer can be added and probed. In this usage scenario, we need to ignore cycles for ensure correctness of sync_state() callbacks. 2. When there are dependency cycles in firmware, we don't know which of those dependencies are valid. So, we have to ignore them all wrt probe ordering while still making sure the sync_state() callbacks come correctly. However, when detecting dependency cycles, there can be multiple dependency cycles between two devices that we need to detect. For example: A -> B -> A and A -> C -> B -> A. To detect multiple cycles correct, we need to be able to differentiate DL_FLAG_SYNC_STATE_ONLY device links used for (1) vs (2) above. To allow this differentiation, add a DL_FLAG_CYCLE that can be use to mark use case (2). We can then use the DL_FLAG_CYCLE to decide which DL_FLAG_SYNC_STATE_ONLY device links to follow when looking for dependency cycles. Fixes: 2de9d8e0d2fe ("driver core: fw_devlink: Improve handling of cyclic dependencies") Signed-off-by: Saravana Kannan Tested-by: Colin Foster Tested-by: Sudeep Holla Tested-by: Douglas Anderson Tested-by: Geert Uytterhoeven Tested-by: Luca Weiss # qcom/sm7225-fairphone-fp4 Link: https://lore.kernel.org/r/20230207014207.1678715-6-saravanak@google.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

driver core: Introduce device_find_any_child() helper

2022-06-10T14:01:55Z

There are several places in the kernel where this kind of functionality is being used. Provide a generic helper for such cases. Reviewed-by: Rafael J. Wysocki Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220610120219.18988-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman

Merge tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2022-06-03T18:48:47Z

Pull driver core updates from Greg KH: "Here is the set of driver core changes for 5.19-rc1. Lots of tiny driver core changes and cleanups happened this cycle, but the two major things are: - firmware_loader reorganization and additions including the ability to have XZ compressed firmware images and the ability for userspace to initiate the firmware load when it needs to, instead of being always initiated by the kernel. FPGA devices specifically want this ability to have their firmware changed over the lifetime of the system boot, and this allows them to work without having to come up with yet-another-custom-uapi interface for loading firmware for them. - physical location support added to sysfs so that devices that know this information, can tell userspace where they are located in a common way. Some ACPI devices already support this today, and more bus types should support this in the future. Smaller changes include: - driver_override api cleanups and fixes - error path cleanups and fixes - get_abi script fixes - deferred probe timeout changes. It's that last change that I'm the most worried about. It has been reported to cause boot problems for a number of systems, and I have a tested patch series that resolves this issue. But I didn't get it merged into my tree before 5.18-final came out, so it has not gotten any linux-next testing. I'll send the fixup patches (there are 2) as a follow-on series to this pull request. All have been tested in linux-next for weeks, with no reported issues other than the above-mentioned boot time-outs" * tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits) driver core: fix deadlock in __device_attach kernfs: Separate kernfs_pr_cont_buf and rename_lock. topology: Remove unused cpu_cluster_mask() driver core: Extend deferred probe timeout on driver registration MAINTAINERS: add Russ Weight as a firmware loader maintainer driver: base: fix UAF when driver_attach failed test_firmware: fix end of loop test in upload_read_show() driver core: location: Add "back" as a possible output for panel driver core: location: Free struct acpi_pld_info *pld driver core: Add "*" wildcard support to driver_async_probe cmdline param driver core: location: Check for allocations failure arch_topology: Trace the update thermal pressure kernfs: Rename kernfs_put_open_node to kernfs_unlink_open_file. export: fix string handling of namespace in EXPORT_SYMBOL_NS rpmsg: use local 'dev' variable rpmsg: Fix calling device_lock() on non-initialized device firmware_loader: describe 'module' parameter of firmware_upload_register() firmware_loader: Move definitions from sysfs_upload.h to sysfs.h firmware_loader: Fix configs for sysfs split selftests: firmware: Add firmware upload selftests ...

device-core: Kill the lockdep_mutex

2022-04-28T21:01:55Z

Per Peter [1], the lockdep API has native support for all the use cases lockdep_mutex was attempting to enable. Now that all lockdep_mutex users have been converted to those APIs, drop this lock. Link: https://lore.kernel.org/r/Ylf0dewci8myLvoW@hirez.programming.kicks-ass.net [1] Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Suggested-by: Peter Zijlstra Reviewed-by: Ira Weiny Acked-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/165055522548.3745911.14298368286915484086.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

cxl/acpi: Add root device lockdep validation

2022-04-28T21:01:54Z

The CXL "root" device, ACPI0017, is an attach point for coordinating platform level CXL resources and is the parent device for a CXL port topology tree. As such it has distinct locking rules relative to other CXL subsystem objects, but because it is an ACPI device the lock class is established well before it is given to the cxl_acpi driver. However, the lockdep API does support changing the lock class "live" for situations like this. Add a device_lock_set_class() helper that a driver can use in ->probe() to set a custom lock class, and device_lock_reset_class() to return to the default "no validate" class before the custom lock class key goes out of scope after ->remove(). Note the helpers are all macros to support dead code elimination in the CONFIG_PROVE_LOCKING=n case, however device_set_lock_class() still needs #ifdef CONFIG_PROVE_LOCKING since lockdep_match_class() explicitly does not have a helper in the CONFIG_PROVE_LOCKING=n case (see comment in lockdep.h). The lockdep API needs 2 small tweaks to prevent "unused" warnings for the @key argument to lock_set_class(), and a new lock_set_novalidate_class() is added to supplement lockdep_set_novalidate_class() in the cases where the lock class is converted while the lock is held. Suggested-by: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Ingo Molnar Cc: Will Deacon Cc: Waiman Long Cc: Boqun Feng Cc: Alison Schofield Cc: Vishal Verma Cc: Ben Widawsky Cc: Jonathan Cameron Reviewed-by: Greg Kroah-Hartman Reviewed-by: Ira Weiny Link: https://lore.kernel.org/r/165100081305.1528964.11138612430659737238.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

driver core: Add sysfs support for physical location of a device

2022-04-27T07:51:57Z

When ACPI table includes _PLD fields for a device, create a new directory (physical_location) in sysfs to share _PLD fields. Currently without PLD information, when there are multiple of same devices, it is hard to distinguish which device corresponds to which physical device at which location. For example, when there are two Type C connectors, it is hard to find out which connector corresponds to the Type C port on the left panel versus the Type C port on the right panel. With PLD information provided, we can determine which specific device at which location is doing what. _PLD output includes much more fields, but only generic fields are added and exposed to sysfs, so that non-ACPI devices can also support it in the future. The minimal generic fields needed for locating a device are the following. - panel - vertical_position - horizontal_position - dock - lid Signed-off-by: Won Chung Link: https://lore.kernel.org/r/20220314195458.271430-1-wonchung@google.com Signed-off-by: Greg Kroah-Hartman

genirq/msi: Move descriptor list to struct msi_device_data

2021-12-16T21:22:16Z

It's only required when MSI is in use. Signed-off-by: Thomas Gleixner Tested-by: Michael Kelley Tested-by: Nishanth Menon Reviewed-by: Greg Kroah-Hartman Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20211206210747.650487479@linutronix.de

device: Add device:: Msi_data pointer and struct msi_device_data

2021-12-16T21:16:38Z

Create struct msi_device_data and add a pointer of that type to struct dev_msi_info, which is part of struct device. Provide an allocator function which can be invoked from the MSI interrupt allocation code pathes. Add a properties field to the data structure as a first member so the allocation size is not zero bytes. The field will be uses later on. Signed-off-by: Thomas Gleixner Tested-by: Michael Kelley Tested-by: Nishanth Menon Reviewed-by: Greg Kroah-Hartman Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20211210221813.676660809@linutronix.de