[PATCH] powerpc: Feed entire flattened device tree into the random pool

[PATCH] powerpc: Feed entire flattened device tree into the random pool

[Anton Blanchard]

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>
---

It might be worth doing this somewhere common, but the only place
I could find (unflatten_device_tree) is almost certainly too
early in the boot process.

diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 63d051f..6914851 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -35,6 +35,7 @@
 #include <linux/percpu.h>
 #include <linux/memblock.h>
 #include <linux/of_platform.h>
+#include <linux/random.h>
 #include <asm/io.h>
 #include <asm/paca.h>
 #include <asm/prom.h>
@@ -752,3 +753,13 @@ void arch_setup_pdev_archdata(struct platform_device *pdev)
 	pdev->dev.dma_mask = &pdev->archdata.dma_mask;
  	set_dma_ops(&pdev->dev, &dma_direct_ops);
 }
+
+/* Feed entire flattened device tree into the random pool */
+static int __init add_fdt_randomness(void)
+{
+	add_device_randomness(initial_boot_params,
+			      initial_boot_params->totalsize);
+
+	return 0;
+}
+core_initcall(add_fdt_randomness);

[PATCH] powerpc: Feed entire flattened device tree into the random pool

[Anton Blanchard]

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>
---

It might be worth doing this somewhere common, but the only place
I could find (unflatten_device_tree) is almost certainly too
early in the boot process.

diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 63d051f..6914851 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -35,6 +35,7 @@
 #include <linux/percpu.h>
 #include <linux/memblock.h>
 #include <linux/of_platform.h>
+#include <linux/random.h>
 #include <asm/io.h>
 #include <asm/paca.h>
 #include <asm/prom.h>
@@ -752,3 +753,13 @@ void arch_setup_pdev_archdata(struct platform_device *pdev)
 	pdev->dev.dma_mask = &pdev->archdata.dma_mask;
  	set_dma_ops(&pdev->dev, &dma_direct_ops);
 }
+
+/* Feed entire flattened device tree into the random pool */
+static int __init add_fdt_randomness(void)
+{
+	add_device_randomness(initial_boot_params,
+			      initial_boot_params->totalsize);
+
+	return 0;
+}
+core_initcall(add_fdt_randomness);

Re: [PATCH] powerpc: Feed entire flattened device tree into the random pool

[Michael Ellerman]

On Thu, Jul 25, 2013 at 12:51:22PM +1000, Anton Blanchard wrote:
> 
> 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>
> ---
> 
> It might be worth doing this somewhere common, but the only place
> I could find (unflatten_device_tree) is almost certainly too
> early in the boot process.

Nice.

But why not put the initcall in drivers/of/fdt.c, that way it's not
early but it's still common ?

cheers

Re: [PATCH] powerpc: Feed entire flattened device tree into the random pool

[Michael Ellerman]

On Thu, Jul 25, 2013 at 12:51:22PM +1000, Anton Blanchard wrote:
> 
> 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>
> ---
> 
> It might be worth doing this somewhere common, but the only place
> I could find (unflatten_device_tree) is almost certainly too
> early in the boot process.

Nice.

But why not put the initcall in drivers/of/fdt.c, that way it's not
early but it's still common ?

cheers

[PATCH] of: Feed entire flattened device tree into the random pool

[Anton Blanchard]

Hi Michael,

> But why not put the initcall in drivers/of/fdt.c, that way it's not
> early but it's still common ?

Good idea! How does this look? So long as it happens before
module_init(rand_initialize) we should be good.

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>
---

v2: move to drivers/of/fdt.c as suggested by Michael Ellerman

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,
+				      initial_boot_params->totalsize);
+
+	return 0;
+}
+core_initcall(add_fdt_randomness);

[PATCH] of: Feed entire flattened device tree into the random pool

[Anton Blanchard]

Hi Michael,

> But why not put the initcall in drivers/of/fdt.c, that way it's not
> early but it's still common ?

Good idea! How does this look? So long as it happens before
module_init(rand_initialize) we should be good.

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>
---

v2: move to drivers/of/fdt.c as suggested by Michael Ellerman

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,
+				      initial_boot_params->totalsize);
+
+	return 0;
+}
+core_initcall(add_fdt_randomness);

Re: [PATCH] of: Feed entire flattened device tree into the random pool

[David Gibson]

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On Thu, Jul 25, 2013 at 02:30:31PM +1000, Anton Blanchard wrote:
> 
> Hi Michael,
> 
> > But why not put the initcall in drivers/of/fdt.c, that way it's not
> > early but it's still common ?
> 
> Good idea! How does this look? So long as it happens before
> module_init(rand_initialize) we should be good.

This must be some strange new meaning of the word "random" of which I
was not previously aware.  But I guess it's marginally better than
nothing.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

[-- Attachment #2: Type: application/pgp-signature, Size: 198 bytes --]

Re: [PATCH] of: Feed entire flattened device tree into the random pool

[David Gibson]

[-- Attachment #1: Type: text/plain, Size: 662 bytes --]

On Thu, Jul 25, 2013 at 02:30:31PM +1000, Anton Blanchard wrote:
> 
> Hi Michael,
> 
> > But why not put the initcall in drivers/of/fdt.c, that way it's not
> > early but it's still common ?
> 
> Good idea! How does this look? So long as it happens before
> module_init(rand_initialize) we should be good.

This must be some strange new meaning of the word "random" of which I
was not previously aware.  But I guess it's marginally better than
nothing.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

[-- Attachment #2: Type: application/pgp-signature, Size: 198 bytes --]

Re: [PATCH] of: Feed entire flattened device tree into the random pool

[Grant Likely]

On Thu, 25 Jul 2013 14:30:31 +1000, Anton Blanchard <anton@samba.org> wrote:
> 
> Hi Michael,
> 
> > But why not put the initcall in drivers/of/fdt.c, that way it's not
> > early but it's still common ?
> 
> Good idea! How does this look? So long as it happens before
> module_init(rand_initialize) we should be good.
> 
> 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>
> ---
> 
> v2: move to drivers/of/fdt.c as suggested by Michael Ellerman
> 
> 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,
> +				      initial_boot_params->totalsize);

be32_to_cpu(initial_boot_params->totalsize);

g.

Re: [PATCH] of: Feed entire flattened device tree into the random pool

[Grant Likely]

On Thu, 25 Jul 2013 14:30:31 +1000, Anton Blanchard <anton@samba.org> wrote:
> 
> Hi Michael,
> 
> > But why not put the initcall in drivers/of/fdt.c, that way it's not
> > early but it's still common ?
> 
> Good idea! How does this look? So long as it happens before
> module_init(rand_initialize) we should be good.
> 
> 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>
> ---
> 
> v2: move to drivers/of/fdt.c as suggested by Michael Ellerman
> 
> 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,
> +				      initial_boot_params->totalsize);

be32_to_cpu(initial_boot_params->totalsize);

g.

Re: [PATCH] of: Feed entire flattened device tree into the random pool

[Anton Blanchard]

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);

Re: [PATCH] of: Feed entire flattened device tree into the random pool

[Anton Blanchard]

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);

Re: [PATCH] of: Feed entire flattened device tree into the random pool

[Grant Likely]

On Mon, 29 Jul 2013 13:11:50 +1000, Anton Blanchard <anton@samba.org> wrote:
> 
> 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>

Applied, thanks

g.