linux-stable.git/drivers/base/swnode.c, branch linux-5.4.y

software node: Let args be NULL in software_node_get_reference_args

2024-01-25T22:34:31+00:00

[ Upstream commit 1eaea4b3604eb9ca7d9a1e73d88fc121bb4061f5 ]

fwnode_get_property_reference_args() may not be called with args argument
NULL and while OF already supports this. Add the missing NULL check.

The purpose is to be able to count the references.

Fixes: b06184acf751 ("software node: Add software_node_get_reference_args()")
Signed-off-by: Sakari Ailus 
Reviewed-by: Andy Shevchenko 
Reviewed-by: Heikki Krogerus 
Link: https://lore.kernel.org/r/20231109101010.1329587-3-sakari.ailus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

software node: Fix node registration

2021-03-17T16:03:48+00:00

commit 8891123f9cbb9c1ee531e5a87fa116f0af685c48 upstream.

Software node can not be registered before its parent.

Fixes: 80488a6b1d3c ("software node: Add support for static node descriptors")
Cc: 5.10+  # 5.10+
Signed-off-by: Heikki Krogerus 
Reviewed-by: Andy Shevchenko 
Tested-by: Andy Shevchenko 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

media: software_node: Fix refcounts in software_node_get_next_child()

2021-03-04T09:26:22+00:00

[ Upstream commit fb5ec981adf08b94e6ce27ca16b7765c94f4513c ]

The software_node_get_next_child() function currently does not hold
references to the child software_node that it finds or put the ref that
is held against the old child - fix that.

Fixes: 59abd83672f7 ("drivers: base: Introducing software nodes to the firmware node framework")
Reviewed-by: Andy Shevchenko 
Reviewed-by: Laurent Pinchart 
Signed-off-by: Daniel Scally 
Reviewed-by: Heikki Krogerus 
Acked-by: Greg Kroah-Hartman 
Acked-by: Rafael J. Wysocki 
Signed-off-by: Sakari Ailus 
Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Sasha Levin

Revert "software node: Simplify software_node_release() function"

2020-05-10T08:31:30+00:00

commit 7589238a8cf37331607c3222a64ac3140b29532d upstream.

This reverts commit 3df85a1ae51f6b256982fe9d17c2dc5bfb4cc402.

The reverted commit says "It's possible to release the node ID
immediately when fwnode_remove_software_node() is called, no need to
wait for software_node_release() with that." However, releasing the node
ID before waiting for software_node_release() to be called causes the
node ID to be released before the kobject and the underlying sysfs
entry; this means there is a period of time where a sysfs entry exists
that is associated with an unallocated node ID.

Once consequence of this is that there is a race condition where it is
possible to call fwnode_create_software_node() with no parent node
specified (NULL) and have it fail with -EEXIST because the node ID that
was assigned is still associated with a stale sysfs entry that hasn't
been cleaned up yet.

Although it is difficult to reproduce this race condition under normal
conditions, it can be deterministically reproduced with the following
minconfig on UML:

CONFIG_KUNIT_DRIVER_PE_TEST=y
CONFIG_DEBUG_KERNEL=y
CONFIG_DEBUG_OBJECTS=y
CONFIG_DEBUG_OBJECTS_TIMERS=y
CONFIG_DEBUG_KOBJECT_RELEASE=y
CONFIG_KUNIT=y

Running the tests with this configuration causes the following failure:


kobject: 'node0' ((____ptrval____)): kobject_release, parent (____ptrval____) (delayed 400)
	ok 1 - pe_test_uints
sysfs: cannot create duplicate filename '/kernel/software_nodes/node0'
CPU: 0 PID: 28 Comm: kunit_try_catch Not tainted 5.6.0-rc3-next-20200227 #14

kobject_add_internal failed for node0 with -EEXIST, don't try to register things with the same name in the same directory.
kobject: 'node0' ((____ptrval____)): kobject_release, parent (____ptrval____) (delayed 100)
	# pe_test_uint_arrays: ASSERTION FAILED at drivers/base/test/property-entry-test.c:123
	Expected node is not error, but is: -17
	not ok 2 - pe_test_uint_arrays


Reported-by: Heidi Fahim 
Signed-off-by: Brendan Higgins 
Reviewed-by: Heikki Krogerus 
Cc: 5.3+  # 5.3+
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

software node: Get reference to parent swnode in get_parent op

2020-01-26T09:01:04+00:00

[ Upstream commit 51c100a651a471fcb8ead1ecc1224471eb0d61b9 ]

The software_node_get_parent() returned a pointer to the parent swnode,
but did not take a reference to it, leading the caller to put a reference
that was not taken. Take that reference now.

Fixes: 59abd83672f7 ("drivers: base: Introducing software nodes to the firmware node framework")
Signed-off-by: Sakari Ailus 
Reviewed-by: Heikki Krogerus 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

software node: Initialize the return value in software_node_find_by_name()

2019-09-11T17:10:12+00:00

The software node is searched from a list that may be empty
when the function is called. This makes sure that the
function returns NULL if the list is empty.

Fixes: 1666faedb567 ("software node: Add software_node_find_by_name()")
Reported-by: kbuild test robot 
Reported-by: Dan Carpenter 
Signed-off-by: Heikki Krogerus 
Reviewed-by: Greg Kroah-Hartman 
Signed-off-by: Rafael J. Wysocki

software node: Initialize the return value in software_node_to_swnode()

2019-09-04T21:03:19+00:00

The software node is searched from a list that may be empty
when the function is called. This makes sure that the
function returns NULL even if the list is empty.

Fixes: 80488a6b1d3c ("software node: Add support for static node descriptors")
Reported-by: kbuild test robot 
Reported-by: Dan Carpenter 
Signed-off-by: Heikki Krogerus 
Reviewed-by: Greg Kroah-Hartman 
Signed-off-by: Rafael J. Wysocki

software node: Add software_node_find_by_name()

2019-08-26T09:35:13+00:00

Function that searches software nodes by node name.

Signed-off-by: Heikki Krogerus 
Reviewed-by: Hans de Goede 
Tested-by: Hans de Goede 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Rafael J. Wysocki

software node: Add software_node_get_reference_args()

2019-06-03T08:55:38+00:00

This makes it possible to support drivers that use
fwnode_property_get_reference_args() function.

Signed-off-by: Heikki Krogerus 
Tested-by: Hans de Goede 
Signed-off-by: Rafael J. Wysocki

software node: Use kobject name when finding child nodes by name

2019-06-03T08:55:38+00:00

Using the kobject name of the node instead of a device
property "name" in software_node_get_named_child_node().

Signed-off-by: Heikki Krogerus 
Tested-by: Hans de Goede 
Signed-off-by: Rafael J. Wysocki