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

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 <geert+renesas@glider.be>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230801-dt-changeset-fixes-v3-2-5f0410e007dd@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 9 insertions, 22 deletions

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index cd3821a6444f..4e436f2d13ae 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -63,15 +63,14 @@ int of_reconfig_notifier_unregister(struct notifier_block *nb)
 }
 EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister);
 
-#ifdef DEBUG
-const char *action_names[] = {
+static const char *action_names[] = {
+	[0] = "INVALID",
 	[OF_RECONFIG_ATTACH_NODE] = "ATTACH_NODE",
 	[OF_RECONFIG_DETACH_NODE] = "DETACH_NODE",
 	[OF_RECONFIG_ADD_PROPERTY] = "ADD_PROPERTY",
 	[OF_RECONFIG_REMOVE_PROPERTY] = "REMOVE_PROPERTY",
 	[OF_RECONFIG_UPDATE_PROPERTY] = "UPDATE_PROPERTY",
 };
-#endif
 
 int of_reconfig_notify(unsigned long action, struct of_reconfig_data *p)
 {
@@ -594,21 +593,9 @@ static int __of_changeset_entry_apply(struct of_changeset_entry *ce)
 		}
 
 		ret = __of_add_property(ce->np, ce->prop);
-		if (ret) {
-			pr_err("changeset: add_property failed @%pOF/%s\n",
-				ce->np,
-				ce->prop->name);
-			break;
-		}
 		break;
 	case OF_RECONFIG_REMOVE_PROPERTY:
 		ret = __of_remove_property(ce->np, ce->prop);
-		if (ret) {
-			pr_err("changeset: remove_property failed @%pOF/%s\n",
-				ce->np,
-				ce->prop->name);
-			break;
-		}
 		break;
 
 	case OF_RECONFIG_UPDATE_PROPERTY:
@@ -622,20 +609,17 @@ static int __of_changeset_entry_apply(struct of_changeset_entry *ce)
 		}
 
 		ret = __of_update_property(ce->np, ce->prop, &old_prop);
-		if (ret) {
-			pr_err("changeset: update_property failed @%pOF/%s\n",
-				ce->np,
-				ce->prop->name);
-			break;
-		}
 		break;
 	default:
 		ret = -EINVAL;
 	}
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
-	if (ret)
+	if (ret) {
+		pr_err("changeset: apply failed: %-15s %pOF:%s\n",
+		       action_names[ce->action], ce->np, ce->prop->name);
 		return ret;
+	}
 
 	switch (ce->action) {
 	case OF_RECONFIG_ATTACH_NODE:
@@ -921,6 +905,9 @@ int of_changeset_action(struct of_changeset *ocs, unsigned long action,
 	if (!ce)
 		return -ENOMEM;
 
+	if (WARN_ON(action >= ARRAY_SIZE(action_names)))
+		return -EINVAL;
+
 	/* get a reference to the node */
 	ce->action = action;
 	ce->np = of_node_get(np);