From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0F070C433DF for ; Thu, 4 Jun 2020 19:36:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E4FAB2075B for ; Thu, 4 Jun 2020 19:36:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="ETG3c85b" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729532AbgFDTgg (ORCPT ); Thu, 4 Jun 2020 15:36:36 -0400 Received: from linux.microsoft.com ([13.77.154.182]:37402 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728420AbgFDTgg (ORCPT ); Thu, 4 Jun 2020 15:36:36 -0400 Received: from jorhand-sb2.corp.microsoft.com (unknown [76.104.235.235]) by linux.microsoft.com (Postfix) with ESMTPSA id 4919820B7185; Thu, 4 Jun 2020 12:36:35 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 4919820B7185 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1591299395; bh=Wj3IFzpGg4vQIux2KK5gfmytqMUrK5JDeB2oZyK7nZ0=; h=From:To:Cc:Subject:Date:From; b=ETG3c85b67XW691yPa3rhCXvFbCy28ekwVUI/3jsxQXpMF+RNf2bQlWPcPS7PflRy umsrgGkv6fO7SIpnQxXH+MFZLOmsh2WU6cIlJoq8XbRi7CsRcWGk6DsKBWGAlHI9rP xNU1On31vVlDKuYro63toACMcMZKqnP9a1S2mXWI= From: jorhand@linux.microsoft.com To: Heikki Krogerus , "Rafael J . Wysocki" Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-next@vger.kernel.org, Jordan Hand Subject: [PATCH] software node: recursively unregister child swnodes Date: Thu, 4 Jun 2020 12:36:23 -0700 Message-Id: <20200604193623.16946-1-jorhand@linux.microsoft.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jordan Hand If a child swnode is unregistered after it's parent, it can lead to undefined behavior. When a swnode is unregistered, recursively free it's children to avoid this condition. Signed-off-by: Jordan Hand --- drivers/base/swnode.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c index e5eb27375416..e63093b1542b 100644 --- a/drivers/base/swnode.c +++ b/drivers/base/swnode.c @@ -619,6 +619,8 @@ static void software_node_release(struct kobject *kobj) property_entries_free(swnode->node->properties); kfree(swnode->node); } + + list_del(&kobj->entry); ida_destroy(&swnode->child_ids); kfree(swnode); } @@ -712,11 +714,6 @@ EXPORT_SYMBOL_GPL(software_node_register_nodes); * @nodes: Zero terminated array of software nodes to be unregistered * * Unregister multiple software nodes at once. - * - * NOTE: Be careful using this call if the nodes had parent pointers set up in - * them before registering. If so, it is wiser to remove the nodes - * individually, in the correct order (child before parent) instead of relying - * on the sequential order of the list of nodes in the array. */ void software_node_unregister_nodes(const struct software_node *nodes) { @@ -839,10 +836,16 @@ EXPORT_SYMBOL_GPL(fwnode_create_software_node); void fwnode_remove_software_node(struct fwnode_handle *fwnode) { struct swnode *swnode = to_swnode(fwnode); + struct swnode *child = NULL; if (!swnode) return; + while (!list_empty(&swnode->children)) { + child = list_first_entry_or_null(&swnode->children, struct swnode, entry); + fwnode_remove_software_node(&child->fwnode); + } + kobject_put(&swnode->kobj); } EXPORT_SYMBOL_GPL(fwnode_remove_software_node); -- 2.17.1