From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754996Ab3KUNpc (ORCPT ); Thu, 21 Nov 2013 08:45:32 -0500 Received: from multi.imgtec.com ([194.200.65.239]:30236 "EHLO multi.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753896Ab3KUNp2 (ORCPT ); Thu, 21 Nov 2013 08:45:28 -0500 From: James Hogan To: Grant Likely , Rob Herring , , CC: , James Hogan Subject: [PATCH v2] of: unflatten_and_copy: handle NULL initial_boot_params Date: Thu, 21 Nov 2013 13:44:14 +0000 Message-ID: <1385041454-32385-1-git-send-email-james.hogan@imgtec.com> X-Mailer: git-send-email 1.8.1.2 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [192.168.154.65] X-SEF-Processed: 7_3_0_01192__2013_11_21_13_45_27 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Check whether initial_boot_params is NULL before dereferencing it in unflatten_and_copy_device_tree() for the case where no device tree is available but the arch can still boot to a minimal usable system without it. In this case also log a warning for when the kernel log buffer is obtainable. Signed-off-by: James Hogan Cc: Grant Likely Cc: Rob Herring Cc: devicetree@vger.kernel.org Cc: linux-arch@vger.kernel.org --- v2: * Log a warning for those who can obtain the kernel log buffer (Grant Likely). --- drivers/of/fdt.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 2fa024b97c43..758b4f8b30b7 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -922,8 +922,16 @@ void __init unflatten_device_tree(void) */ void __init unflatten_and_copy_device_tree(void) { - int size = __be32_to_cpu(initial_boot_params->totalsize); - void *dt = early_init_dt_alloc_memory_arch(size, + int size; + void *dt; + + if (!initial_boot_params) { + pr_warn("No valid device tree found, continuing without\n"); + return; + } + + size = __be32_to_cpu(initial_boot_params->totalsize); + dt = early_init_dt_alloc_memory_arch(size, __alignof__(struct boot_param_header)); if (dt) { -- 1.8.1.2