kernel/linux.git/drivers/of/dynamic.c, branch v6.1.175

device property: Make modifications of fwnode "flags" thread safe

2026-06-01T15:38:45+00:00

commit f72e77c33e4b5657af35125e75bab249256030f3 upstream. In various places in the kernel, we modify the fwnode "flags" member by doing either: fwnode->flags |= SOME_FLAG; fwnode->flags &= ~SOME_FLAG; This type of modification is not thread-safe. If two threads are both mucking with the flags at the same time then one can clobber the other. While flags are often modified while under the "fwnode_link_lock", this is not universally true. Create some accessor functions for setting, clearing, and testing the FWNODE flags and move all users to these accessor functions. New accessor functions use set_bit() and clear_bit(), which are thread-safe. Cc: stable@vger.kernel.org Fixes: c2c724c868c4 ("driver core: Add fw_devlink_parse_fwtree()") Reviewed-by: Andy Shevchenko Acked-by: Mark Brown Reviewed-by: Wolfram Sang Signed-off-by: Douglas Anderson Reviewed-by: Rafael J. Wysocki (Intel) Reviewed-by: Saravana Kannan Link: https://patch.msgid.link/20260317090112.v2.1.I0a4d03104ecd5103df3d76f66c8d21b1d15a2e38@changeid [ Fix fwnode_clear_flag() argument alignment, restore dropped blank line in fwnode_dev_initialized(), and remove unnecessary parentheses around fwnode_test_flag() calls. - Danilo ] Signed-off-by: Danilo Krummrich Signed-off-by: Douglas Anderson Signed-off-by: Greg Kroah-Hartman

of: dynamic: Synchronize of_changeset_destroy() with the devlink removals

2024-04-10T14:28:32+00:00

commit 8917e7385346bd6584890ed362985c219fe6ae84 upstream. In the following sequence: 1) of_platform_depopulate() 2) of_overlay_remove() During the step 1, devices are destroyed and devlinks are removed. During the step 2, OF nodes are destroyed but __of_changeset_entry_destroy() can raise warnings related to missing of_node_put(): ERROR: memory leak, expected refcount 1 instead of 2 ... Indeed, during the devlink removals performed at step 1, the removal itself releasing the device (and the attached of_node) is done by a job queued in a workqueue and so, it is done asynchronously with respect to function calls. When the warning is present, of_node_put() will be called but wrongly too late from the workqueue job. In order to be sure that any ongoing devlink removals are done before the of_node destruction, synchronize the of_changeset_destroy() with the devlink removals. Fixes: 80dd33cf72d1 ("drivers: base: Fix device link removal") Cc: stable@vger.kernel.org Signed-off-by: Herve Codina Reviewed-by: Saravana Kannan Tested-by: Luca Ceresoli Reviewed-by: Nuno Sa Link: https://lore.kernel.org/r/20240325152140.198219-3-herve.codina@bootlin.com Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

of: dynamic: Fix of_reconfig_get_state_change() return value documentation

2023-12-13T17:39:05+00:00

[ Upstream commit d79972789d17499b6091ded2fc0c6763c501a5ba ] The documented numeric return values do not match the actual returned values. Fix them by using the enum names instead of raw numbers. Fixes: b53a2340d0d3 ("of/reconfig: Add of_reconfig_get_state_change() of notifier helper.") Signed-off-by: Luca Ceresoli Link: https://lore.kernel.org/r/20231123-fix-of_reconfig_get_state_change-docs-v1-1-f51892050ff9@bootlin.com Signed-off-by: Rob Herring Signed-off-by: Sasha Levin

of: dynamic: Fix potential memory leak in of_changeset_action()

2023-10-10T20:00:44+00:00

commit 55e95bfccf6db8d26a66c46e1de50d53c59a6774 upstream. Smatch complains that the error path where "action" is invalid leaks the "ce" allocation: drivers/of/dynamic.c:935 of_changeset_action() warn: possible memory leak of 'ce' Fix this by doing the validation before the allocation. Note that there is not any actual problem with upstream kernels. All callers of of_changeset_action() are static inlines with fixed action values. Fixes: 914d9d831e61 ("of: dynamic: Refactor action prints to not use "%pOF" inside devtree_lock") Reported-by: kernel test robot Closes: https://lore.kernel.org/r/202309011059.EOdr4im9-lkp@intel.com/ Signed-off-by: Dan Carpenter Reviewed-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/7dfaf999-30ad-491c-9615-fb1138db121c@moroto.mountain Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

treewide: Fix probing of devices in DT overlays

2023-09-13T07:43:05+00:00

commit 1a50d9403fb90cbe4dea0ec9fd0351d2ecbd8924 upstream. When loading a DT overlay that creates a device, the device is not probed, unless the DT overlay is unloaded and reloaded again. After the recent refactoring to improve fw_devlink, it no longer depends on the "compatible" property to identify which device tree nodes will become struct devices. fw_devlink now picks up dangling consumers (consumers pointing to descendent device tree nodes of a device that aren't converted to child devices) when a device is successfully bound to a driver. See __fw_devlink_pickup_dangling_consumers(). However, during DT overlay, a device's device tree node can have sub-nodes added/removed without unbinding/rebinding the driver. This difference in behavior between the normal device instantiation and probing flow vs. the DT overlay flow has a bunch of implications that are pointed out elsewhere[1]. One of them is that the fw_devlink logic to pick up dangling consumers is never exercised. This patch solves the fw_devlink issue by marking all DT nodes added by DT overlays with FWNODE_FLAG_NOT_DEVICE (fwnode that won't become device), and by clearing the flag when a struct device is actually created for the DT node. This way, fw_devlink knows not to have consumers waiting on these newly added DT nodes, and to propagate the dependency to an ancestor DT node that has the corresponding struct device. Based on a patch by Saravana Kannan, which covered only platform and spi devices. [1] https://lore.kernel.org/r/CAGETcx_bkuFaLCiPrAWCPQz+w79ccDp6=9e881qmK=vx3hBMyg@mail.gmail.com Fixes: 4a032827daa89350 ("of: property: Simplify of_link_to_phandle()") Link: https://lore.kernel.org/r/CAGETcx_+rhHvaC_HJXGrr5_WAd2+k5f=rWYnkCZ6z5bGX-wj4w@mail.gmail.com Signed-off-by: Geert Uytterhoeven Acked-by: Mark Brown Acked-by: Wolfram Sang # for I2C Acked-by: Shawn Guo Acked-by: Saravana Kannan Tested-by: Ivan Bornyakov Link: https://lore.kernel.org/r/e1fa546682ea4c8474ff997ab6244c5e11b6f8bc.1680182615.git.geert+renesas@glider.be Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

of: dynamic: Refactor action prints to not use "%pOF" inside devtree_lock

2023-08-30T14:11:08+00:00

commit 914d9d831e6126a6e7a92e27fcfaa250671be42c upstream. While originally it was fine to format strings using "%pOF" while holding devtree_lock, this now causes a deadlock. Lockdep reports: of_get_parent from of_fwnode_get_parent+0x18/0x24 ^^^^^^^^^^^^^ of_fwnode_get_parent from fwnode_count_parents+0xc/0x28 fwnode_count_parents from fwnode_full_name_string+0x18/0xac fwnode_full_name_string from device_node_string+0x1a0/0x404 device_node_string from pointer+0x3c0/0x534 pointer from vsnprintf+0x248/0x36c vsnprintf from vprintk_store+0x130/0x3b4 Fix this by moving the printing in __of_changeset_entry_apply() outside the lock. As the only difference in the multiple prints is the action name, use the existing "action_names" to refactor the prints into a single print. Fixes: a92eb7621b9fb2c2 ("lib/vsprintf: Make use of fwnode API to obtain node names and separators") Cc: stable@vger.kernel.org Reported-by: Geert Uytterhoeven Reviewed-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/20230801-dt-changeset-fixes-v3-2-5f0410e007dd@kernel.org Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

of: Add missing 'Return' section in kerneldoc comments

2021-03-27T18:59:03+00:00

Many of the DT kerneldoc comments are lacking a 'Return' section. Let's add the section in cases we have a description of return values. There's still some cases where the return values are not documented. Cc: Frank Rowand Cc: Mauro Carvalho Chehab Signed-off-by: Rob Herring Reviewed-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/20210325164713.1296407-8-robh@kernel.org

of: dynamic: Fix incorrect parameter name and provide missing descriptions

2021-03-23T21:27:52+00:00

Fixes the following W=1 kernel build warning(s): drivers/of/dynamic.c:234: warning: Function parameter or member 'np' not described in 'of_attach_node' drivers/of/dynamic.c:286: warning: Function parameter or member 'np' not described in 'of_detach_node' drivers/of/dynamic.c:326: warning: Function parameter or member 'kobj' not described in 'of_node_release' drivers/of/dynamic.c:326: warning: Excess function parameter 'kref' description in 'of_node_release' Cc: Rob Herring Cc: Frank Rowand Cc: devicetree@vger.kernel.org Signed-off-by: Lee Jones Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20210318104036.3175910-3-lee.jones@linaro.org

driver core: Add fwnode link support

2020-12-09T18:10:21+00:00

Add support for creating supplier-consumer links between fwnodes. It is intended for internal use the driver core and generic firmware support code (eg. Device Tree, ACPI), so it is simple by design and the API provided is limited. Acked-by: Rob Herring Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-9-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

of: of_detach_node() remove unneeded local return variable

2020-04-14T12:59:54+00:00

rc is unneeded, just return 0. Signed-off-by: Ding Xiang Signed-off-by: Rob Herring