Merge tag 'acpi-5.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI fixes from Rafael Wysocki:
 "These fix a NULL pointer dereference in the CPPC library code and a
  locking issue related to printing the names of ACPI device nodes in
  the device properties framework.

  Specifics:

   - Fix NULL pointer dereference in the CPPC library code occuring on
     hybrid systems without CPPC support (Rafael Wysocki).

   - Avoid attempts to acquire a semaphore with interrupts off when
     printing the names of ACPI device nodes and clean up code on top of
     that fix (Sakari Ailus)"

* tag 'acpi-5.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: CPPC: Add NULL pointer check to cppc_get_perf()
  ACPI: Make acpi_node_get_parent() local
  ACPI: Get acpi_device's parent from the parent field

Author: torvalds

drivers/acpi/cppc_acpi.c

@@ -998,7 +998,14 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val)
 static int cppc_get_perf(int cpunum, enum cppc_regs reg_idx, u64 *perf)
 {
 	struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpunum);
-	struct cpc_register_resource *reg = &cpc_desc->cpc_regs[reg_idx];
+	struct cpc_register_resource *reg;
+
+	if (!cpc_desc) {
+		pr_debug("No CPC descriptor for CPU:%d\n", cpunum);
+		return -ENODEV;
+	}
+
+	reg = &cpc_desc->cpc_regs[reg_idx];
 
 	if (CPC_IN_PCC(reg)) {
 		int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpunum);

drivers/acpi/property.c

@@ -1084,21 +1084,17 @@ struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
  * Returns parent node of an ACPI device or data firmware node or %NULL if
  * not available.
  */
-struct fwnode_handle *acpi_node_get_parent(const struct fwnode_handle *fwnode)
+static struct fwnode_handle *
+acpi_node_get_parent(const struct fwnode_handle *fwnode)
 {
 	if (is_acpi_data_node(fwnode)) {
 		/* All data nodes have parent pointer so just return that */
 		return to_acpi_data_node(fwnode)->parent;
 	} else if (is_acpi_device_node(fwnode)) {
-		acpi_handle handle, parent_handle;
-
-		handle = to_acpi_device_node(fwnode)->handle;
-		if (ACPI_SUCCESS(acpi_get_parent(handle, &parent_handle))) {
-			struct acpi_device *adev;
+		struct device *dev = to_acpi_device_node(fwnode)->dev.parent;
 
-			if (!acpi_bus_get_device(parent_handle, &adev))
-				return acpi_fwnode_handle(adev);
-		}
+		if (dev)
+			return acpi_fwnode_handle(to_acpi_device(dev));
 	}
 
 	return NULL;

include/linux/acpi.h

@@ -1182,7 +1182,6 @@ int acpi_node_prop_get(const struct fwnode_handle *fwnode, const char *propname,
 
 struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
 					    struct fwnode_handle *child);
-struct fwnode_handle *acpi_node_get_parent(const struct fwnode_handle *fwnode);
 
 struct acpi_probe_entry;
 typedef bool (*acpi_probe_entry_validate_subtbl)(struct acpi_subtable_header *,
@@ -1287,12 +1286,6 @@ acpi_get_next_subnode(const struct fwnode_handle *fwnode,
 	return NULL;
 }
 
-static inline struct fwnode_handle *
-acpi_node_get_parent(const struct fwnode_handle *fwnode)
-{
-	return NULL;
-}
-
 static inline struct fwnode_handle *
 acpi_graph_get_next_endpoint(const struct fwnode_handle *fwnode,
 			     struct fwnode_handle *prev)