kernel/drivers/base, branch linux-rolling-stable

device property: Allow secondary lookup in fwnode_get_next_child_node()

2026-03-19T15:15:15Z

commit 2692c614f8f05929d692b3dbfd3faef1f00fbaf0 upstream. When device_get_child_node_count() got split to the fwnode and device respective APIs, the fwnode didn't inherit the ability to traverse over the secondary fwnode. Hence any user, that switches from device to fwnode API misses this feature. In particular, this was revealed by the commit 1490cbb9dbfd ("device property: Split fwnode_get_child_node_count()") that effectively broke the GPIO enumeration on Intel Galileo boards. Fix this by moving the secondary lookup from device to fwnode API. Note, in general no device_*() API should go into the depth of the fwnode implementation. Fixes: 114dbb4fa7c4 ("drivers property: When no children in primary, try secondary") Cc: stable@vger.kernel.org Signed-off-by: Andy Shevchenko Reviewed-by: Rafael J. Wysocki (Intel) Reviewed-by: Sakari Ailus Link: https://patch.msgid.link/20260210135822.47335-1-andriy.shevchenko@linux.intel.com Signed-off-by: Danilo Krummrich Signed-off-by: Greg Kroah-Hartman

driver core: faux: stop using static struct device

2026-03-04T12:20:27Z

[ Upstream commit 61b76d07d2b46a86ea91267d36449fc78f8a1f6e ] faux_bus_root should not have been a static struct device, but rather a dynamically created structure so that lockdep and other testing tools do not trip over it (as well as being the right thing overall to do.) Fix this up by making it properly dynamic. Reported-by: Gui-Dong Han Closes: https://lore.kernel.org/lkml/CALbr=LYKJsj6cbrDLA07qioKhWJcRj+gW8=bq5=4ZvpEe2c4Yg@mail.gmail.com/ Reviewed-by: Danilo Krummrich Link: https://patch.msgid.link/2026012145-lapping-countless-ef81@gregkh Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

PM: sleep: wakeirq: harden dev_pm_clear_wake_irq() against races

2026-02-26T23:00:44Z

[ Upstream commit 5c9ecd8e6437cd55a38ea4f1e1d19cee8e226cb8 ] dev_pm_clear_wake_irq() currently uses a dangerous pattern where dev->power.wakeirq is read and checked for NULL outside the lock. If two callers invoke this function concurrently, both might see a valid pointer and proceed. This could result in a double-free when the second caller acquires the lock and tries to release the same object. Address this by removing the lockless check of dev->power.wakeirq. Instead, acquire dev->power.lock immediately to ensure the check and the subsequent operations are atomic. If dev->power.wakeirq is NULL under the lock, simply unlock and return. This guarantees that concurrent calls cannot race to free the same object. Based on a quick scan of current users, I did not find an actual bug as drivers seem to rely on their own synchronization. However, since asynchronous usage patterns exist (e.g., in drivers/net/wireless/ti/wlcore), I believe a race is theoretically possible if the API is used less carefully in the future. This change hardens the API to be robust against such cases. Fixes: 4990d4fe327b ("PM / Wakeirq: Add automated device wake IRQ handling") Signed-off-by: Gui-Dong Han Link: https://patch.msgid.link/20260203031943.1924-1-hanguidong02@gmail.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

PM: wakeup: Handle empty list in wakeup_sources_walk_start()

2026-02-26T23:00:44Z

[ Upstream commit 75ce02f4bc9a8b8350b6b1b01872467b0cc960cc ] In the case of an empty wakeup_sources list, wakeup_sources_walk_start() will return an invalid but non-NULL address. This also affects wrappers of the aforementioned function, like for_each_wakeup_source(). Update wakeup_sources_walk_start() to return NULL in case of an empty list. Fixes: b4941adb24c0 ("PM: wakeup: Add routine to help fetch wakeup source object.") Signed-off-by: Samuel Wu [ rjw: Subject and changelog edits ] Link: https://patch.msgid.link/20260124012133.2451708-2-wusamuel@google.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

Revert "driver core: enforce device_lock for driver_match_device()"

2026-02-16T16:11:45Z

This reverts commit bc82e5f4d7dc8237ae8cabc73aa46fc93c85d98c which is commit dc23806a7c47ec5f1293aba407fb69519f976ee0 upstream. It causes boot regressions on some systems as all of the "fixes" for drivers are not properly backported yet. Once that is completed, only then can this be applied, if really necessary given the potential for explosions, perhaps we might want to wait a few -rc releases first... Cc: Danilo Krummrich Cc: Rafael J. Wysocki (Intel) Cc: Danilo Krummrich Cc: Gui-Dong Han Cc: Qiu-ji Chen Reported-by: Mark Brown Link: https://lore.kernel.org/r/7dfd0e63-a725-4fac-b2a0-f2e621d99d1b@sirena.org.uk Signed-off-by: Greg Kroah-Hartman

driver core: enforce device_lock for driver_match_device()

2026-02-16T09:13:31Z

commit dc23806a7c47ec5f1293aba407fb69519f976ee0 upstream. Currently, driver_match_device() is called from three sites. One site (__device_attach_driver) holds device_lock(dev), but the other two (bind_store and __driver_attach) do not. This inconsistency means that bus match() callbacks are not guaranteed to be called with the lock held. Fix this by introducing driver_match_device_locked(), which guarantees holding the device lock using a scoped guard. Replace the unlocked calls in bind_store() and __driver_attach() with this new helper. Also add a lock assertion to driver_match_device() to enforce this guarantee. This consistency also fixes a known race condition. The driver_override implementation relies on the device_lock, so the missing lock led to the use-after-free (UAF) reported in Bugzilla for buses using this field. Stress testing the two newly locked paths for 24 hours with CONFIG_PROVE_LOCKING and CONFIG_LOCKDEP enabled showed no UAF recurrence and no lockdep warnings. Cc: stable@vger.kernel.org Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220789 Suggested-by: Qiu-ji Chen Signed-off-by: Gui-Dong Han Fixes: 49b420a13ff9 ("driver core: check bus->match without holding device lock") Reviewed-by: Danilo Krummrich Reviewed-by: Greg Kroah-Hartman Reviewed-by: Rafael J. Wysocki (Intel) Link: https://patch.msgid.link/20260113162843.12712-1-hanguidong02@gmail.com Signed-off-by: Danilo Krummrich Signed-off-by: Greg Kroah-Hartman

Merge tag 'driver-core-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core

2026-01-24T18:13:22Z

Pull driver core fixes from Danilo Krummrich: - Always inline I/O and IRQ methods using build_assert!() to avoid false positive build errors - Do not free the driver's device private data in I2C shutdown() avoiding race conditions that can lead to UAF bugs - Drop the driver's device private data after the driver has been fully unbound from its device to avoid UAF bugs from &Device scopes, such as IRQ callbacks * tag 'driver-core-6.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: rust: driver: drop device private data post unbind rust: driver: add DriverData type to the DriverLayout trait rust: driver: add DEVICE_DRIVER_OFFSET to the DriverLayout trait rust: driver: introduce a DriverLayout trait rust: auxiliary: add Driver::unbind() callback rust: i2c: do not drop device private data on shutdown() rust: irq: always inline functions using build_assert with arguments rust: io: always inline functions using build_assert with arguments

rust: driver: drop device private data post unbind

2026-01-16T00:17:29Z

Currently, the driver's device private data is allocated and initialized from driver core code called from bus abstractions after the driver's probe() callback returned the corresponding initializer. Similarly, the driver's device private data is dropped within the remove() callback of bus abstractions after calling the remove() callback of the corresponding driver. However, commit 6f61a2637abe ("rust: device: introduce Device::drvdata()") introduced an accessor for the driver's device private data for a Device, i.e. a device that is currently bound to a driver. Obviously, this is in conflict with dropping the driver's device private data in remove(), since a device can not be considered to be fully unbound after remove() has finished: We also have to consider registrations guarded by devres - such as IRQ or class device registrations - which are torn down after remove() in devres_release_all(). Thus, it can happen that, for instance, a class device or IRQ callback still calls Device::drvdata(), which then runs concurrently to remove() (which sets dev->driver_data to NULL and drops the driver's device private data), before devres_release_all() started to tear down the corresponding registration. This is because devres guarded registrations can, as expected, access the corresponding Device that defines their scope. In C it simply is the driver's responsibility to ensure that its device private data is freed after e.g. an IRQ registration is unregistered. Typically, C drivers achieve this by allocating their device private data with e.g. devm_kzalloc() before doing anything else, i.e. before e.g. registering an IRQ with devm_request_threaded_irq(), relying on the reverse order cleanup of devres. Technically, we could do something similar in Rust. However, the resulting code would be pretty messy: In Rust we have to differentiate between allocated but uninitialized memory and initialized memory in the type system. Thus, we would need to somehow keep track of whether the driver's device private data object has been initialized (i.e. probe() was successful and returned a valid initializer for this memory) and conditionally call the destructor of the corresponding object when it is freed. This is because we'd need to allocate and register the memory of the driver's device private data *before* it is initialized by the initializer returned by the driver's probe() callback, because the driver could already register devres guarded registrations within probe() outside of the driver's device private data initializer. Luckily there is a much simpler solution: Instead of dropping the driver's device private data at the end of remove(), we just drop it after the device has been fully unbound, i.e. after all devres callbacks have been processed. For this, we introduce a new post_unbind() callback private to the driver-core, i.e. the callback is neither exposed to drivers, nor to bus abstractions. This way, the driver-core code can simply continue to conditionally allocate the memory for the driver's device private data when the driver's initializer is returned from probe() - no change needed - and drop it when the driver-core code receives the post_unbind() callback. Closes: https://lore.kernel.org/all/DEZMS6Y4A7XE.XE7EUBT5SJFJ@kernel.org/ Fixes: 6f61a2637abe ("rust: device: introduce Device::drvdata()") Acked-by: Alice Ryhl Acked-by: Greg Kroah-Hartman Acked-by: Igor Korotin Link: https://patch.msgid.link/20260107103511.570525-7-dakr@kernel.org [ Remove #ifdef CONFIG_RUST, rename post_unbind() to post_unbind_rust(). - Danilo] Signed-off-by: Danilo Krummrich

regmap: Fix race condition in hwspinlock irqsave routine

2026-01-12T12:25:29Z

Previously, the address of the shared member '&map->spinlock_flags' was passed directly to 'hwspin_lock_timeout_irqsave'. This creates a race condition where multiple contexts contending for the lock could overwrite the shared flags variable, potentially corrupting the state for the current lock owner. Fix this by using a local stack variable 'flags' to store the IRQ state temporarily. Fixes: 8698b9364710 ("regmap: Add hardware spinlock support") Signed-off-by: Cheng-Yu Lee Co-developed-by: Yu-Chun Lin Signed-off-by: Yu-Chun Lin Link: https://patch.msgid.link/20260109032633.8732-1-eleanor.lin@realtek.com Signed-off-by: Mark Brown

regmap: maple: free entry on mas_store_gfp() failure

2026-01-05T13:14:50Z

regcache_maple_write() allocates a new block ('entry') to merge adjacent ranges and then stores it with mas_store_gfp(). When mas_store_gfp() fails, the new 'entry' remains allocated and is never freed, leaking memory. Free 'entry' on the failure path; on success continue freeing the replaced neighbor blocks ('lower', 'upper'). Signed-off-by: Kaushlendra Kumar Link: https://patch.msgid.link/20260105031820.260119-1-kaushlendra.kumar@intel.com Signed-off-by: Mark Brown