From patchwork Mon Jul 29 03:11:50 2013
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
X-Patchwork-Submitter: Anton Blanchard <anton@samba.org>
X-Patchwork-Id: 262650
Return-Path: 
 <linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org>
X-Original-To: patchwork-incoming@ozlabs.org
Delivered-To: patchwork-incoming@ozlabs.org
Received: from ozlabs.org (localhost [IPv6:::1])
	by ozlabs.org (Postfix) with ESMTP id 485512C0125
	for <patchwork-incoming@ozlabs.org>;
	Mon, 29 Jul 2013 13:12:34 +1000 (EST)
Received: from kryten (ppp121-44-48-234.lns20.syd6.internode.on.net
	[121.44.48.234])
	(using SSLv3 with cipher DHE-RSA-AES128-SHA (128/128 bits))
	(Client did not present a certificate)
	by ozlabs.org (Postfix) with ESMTPSA id E98A82C0099;
	Mon, 29 Jul 2013 13:12:04 +1000 (EST)
Date: Mon, 29 Jul 2013 13:11:50 +1000
From: Anton Blanchard <anton@samba.org>
To: Grant Likely <grant.likely@linaro.org>
Subject: Re: [PATCH] of: Feed entire flattened device tree into the random
	pool
Message-ID: <20130729131150.591926c3@kryten>
In-Reply-To: <20130728044942.A58793E0A24@localhost>
References: <20130725125122.78accf44@kryten>
	<20130725031717.GB15673@concordia>
	<20130725143031.16af0a96@kryten>
	<20130728044942.A58793E0A24@localhost>
X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.17; x86_64-pc-linux-gnu)
Mime-Version: 1.0
Cc: devicetree@vger.kernel.org, Rob Herring <rob.herring@calxeda.com>,
	Paul Mackerras <paulus@samba.org>, linuxppc-dev@lists.ozlabs.org
X-BeenThere: linuxppc-dev@lists.ozlabs.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Linux on PowerPC Developers Mail List
	<linuxppc-dev.lists.ozlabs.org>
List-Unsubscribe: <https://lists.ozlabs.org/options/linuxppc-dev>,
	<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=unsubscribe>
List-Archive: <http://lists.ozlabs.org/pipermail/linuxppc-dev/>
List-Post: <mailto:linuxppc-dev@lists.ozlabs.org>
List-Help: <mailto:linuxppc-dev-request@lists.ozlabs.org?subject=help>
List-Subscribe: <https://lists.ozlabs.org/listinfo/linuxppc-dev>,
	<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=subscribe>
Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org
Sender: "Linuxppc-dev"
	<linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org>

Hi,

> be32_to_cpu(initial_boot_params->totalsize);

Ouch, thanks Grant.

Anton
---

We feed the entire DMI table into the random pool to provide
better random data during early boot, so do the same with the
flattened device tree.

Signed-off-by: Anton Blanchard <anton@samba.org>
---

v3: Fix endian issues as noted by Grant

Index: b/drivers/of/fdt.c
===================================================================
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -17,6 +17,7 @@
 #include <linux/string.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
+#include <linux/random.h>
 
 #include <asm/setup.h>  /* for COMMAND_LINE_SIZE */
 #ifdef CONFIG_PPC
@@ -714,3 +715,14 @@ void __init unflatten_device_tree(void)
 }
 
 #endif /* CONFIG_OF_EARLY_FLATTREE */
+
+/* Feed entire flattened device tree into the random pool */
+static int __init add_fdt_randomness(void)
+{
+	if (initial_boot_params)
+		add_device_randomness(initial_boot_params,
+				be32_to_cpu(initial_boot_params->totalsize));
+
+	return 0;
+}
+core_initcall(add_fdt_randomness);