Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755888Ab3HLLCE (ORCPT ); Mon, 12 Aug 2013 07:02:04 -0400 Received: from mail-we0-f173.google.com ([74.125.82.173]:37873 "EHLO mail-we0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752298Ab3HLLCB (ORCPT ); Mon, 12 Aug 2013 07:02:01 -0400 Message-ID: <5208C04A.5000303@gmail.com> Date: Mon, 12 Aug 2013 13:00:26 +0200 From: Wladislav Wiebe User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130308 Thunderbird/17.0.4 MIME-Version: 1.0 To: grant.likely@linaro.org, rob.herring@calxeda.com, devicetree@vger.kernel.org CC: linux-kernel@vger.kernel.org Subject: [PATCH 1/1] of: fdt: fix memory initialization for expanded DT Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1910 Lines: 51 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 --- drivers/of/fdt.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 6bb7cf2..b10ba00 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -392,6 +392,8 @@ 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); -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/