linux-kernel - [PATCH 1/1] ACPI: property: Return present device nodes only on fwnode interface

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251001102636.1272722-2-sakari.ailus@linux.intel.com>
Date: Wed,  1 Oct 2025 13:26:36 +0300
From: Sakari Ailus <sakari.ailus@...ux.intel.com>
To: linux-acpi@...r.kernel.org
Cc: linux-kernel@...r.kernel.org,
	"Rafael J. Wysocki" <rafael@...nel.org>,
	Len Brown <lenb@...nel.org>,
	Dmitry Torokhov <dmitry.torokhov@...il.com>,
	Laurent Pinchart <laurent.pinchart@...asonboard.com>,
	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
	Jonathan Cameron <Jonathan.Cameron@...wei.com>
Subject: [PATCH 1/1] ACPI: property: Return present device nodes only on fwnode interface

fwnode_graph_get_next_subnode() may return fwnode backed by ACPI device
nodes and there has been no check these devices are present in the system,
unlike there has been on fwnode OF backend. In order to provide consistent
behaviour towards callers, add a check for device presence by introducing
a new function acpi_get_next_present_subnode(), used as the
get_next_child_node() fwnode operation that also checks device node
presence.

Signed-off-by: Sakari Ailus <sakari.ailus@...ux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@...asonboard.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@...wei.com>
---
 drivers/acpi/property.c | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 436019d96027..10bab30300f3 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -1318,6 +1318,28 @@ struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
 	return NULL;
 }
 
+/*
+ * acpi_get_next_present_subnode - Return the next present child node handle for a fwnode
+ * @fwnode: Firmware node to find the next child node for.
+ * @child: Handle to one of the device's child nodes or a null handle.
+ *
+ * Like acpi_get_next_subnode(), but the device nodes returned by
+ * acpi_get_next_present_subnode() are guaranteed to be present.
+ *
+ * Returns: The next sub-node fwnode handle.
+ */
+static struct fwnode_handle *
+acpi_get_next_present_subnode(const struct fwnode_handle *fwnode,
+			      struct fwnode_handle *child)
+{
+	do {
+		child = acpi_get_next_subnode(fwnode, child);
+	} while (is_acpi_device_node(child) &&
+		 !acpi_device_is_present(to_acpi_device_node(child)));
+
+	return child;
+}
+
 /**
  * acpi_node_get_parent - Return parent fwnode of this fwnode
  * @fwnode: Firmware node whose parent to get
@@ -1662,7 +1684,7 @@ static int acpi_fwnode_irq_get(const struct fwnode_handle *fwnode,
 		.property_read_string_array =				\
 			acpi_fwnode_property_read_string_array,		\
 		.get_parent = acpi_node_get_parent,			\
-		.get_next_child_node = acpi_get_next_subnode,		\
+		.get_next_child_node = acpi_get_next_present_subnode,	\
 		.get_named_child_node = acpi_fwnode_get_named_child_node, \
 		.get_name = acpi_fwnode_get_name,			\
 		.get_name_prefix = acpi_fwnode_get_name_prefix,		\
-- 
2.47.3