From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758795Ab3IBJCO (ORCPT ); Mon, 2 Sep 2013 05:02:14 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:37832 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758419Ab3IBIzh (ORCPT ); Mon, 2 Sep 2013 04:55:37 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Wladislav Wiebe , Rob Herring , Luis Henriques Subject: [PATCH 44/58] of: fdt: fix memory initialization for expanded DT Date: Mon, 2 Sep 2013 09:54:29 +0100 Message-Id: <1378112083-9475-45-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1378112083-9475-1-git-send-email-luis.henriques@canonical.com> References: <1378112083-9475-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.21 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Wladislav Wiebe commit 9e40127526e857fa3f29d51e83277204fbdfc6ba upstream. Already existing property flags are filled wrong for properties created from initial FDT. This could cause problems if this DYNAMIC device-tree functions are used later, i.e. properties are attached/detached/replaced. Simply dumping flags from the running system show, that some initial static (not allocated via kzmalloc()) nodes are marked as dynamic. I putted some debug extensions to property_proc_show(..) : .. + if (OF_IS_DYNAMIC(pp)) + pr_err("DEBUG: xxx : OF_IS_DYNAMIC\n"); + if (OF_IS_DETACHED(pp)) + pr_err("DEBUG: xxx : OF_IS_DETACHED\n"); when you operate on the nodes (e.g.: ~$ cat /proc/device-tree/*some_node*) you will see that those flags are filled wrong, basically in most cases it will dump a DYNAMIC or DETACHED status, which is in not true. (BTW. this OF_IS_DETACHED is a own define for debug purposes which which just make a test_bit(OF_DETACHED, &x->_flags) If nodes are dynamic kernel is allowed to kfree() them. But it will crash attempting to do so on the nodes from FDT -- they are not allocated via kzmalloc(). Signed-off-by: Wladislav Wiebe Acked-by: Alexander Sverdlin Signed-off-by: Rob Herring Signed-off-by: Luis Henriques --- drivers/of/fdt.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 91a375f..17fad3b 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -390,6 +390,8 @@ static void __unflatten_device_tree(struct boot_param_header *blob, mem = (unsigned long) dt_alloc(size + 4, __alignof__(struct device_node)); + memset((void *)mem, 0, size); + ((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef); pr_debug(" unflattening %lx...\n", mem); -- 1.8.3.2