Re: [PATCH v2 3/3] powerpc/pseries: wire up rng during setup_arch

[Christophe Leroy <christophe.leroy@csgroup.eu>]

Le 11/06/2022 à 12:04, Jason A. Donenfeld a écrit :
> The platform's RNG must be available before random_init() in order to be
> useful for initial seeding, which in turn means that it needs to be
> called from setup_arch(), rather than from an init call. Fortunately,
> each platform already has a setup_arch function pointer, which means
> it's easy to wire this up for each of the three platforms that have an
> RNG. This commit also removes some noisy log messages that don't add
> much.
> 
> Cc: stable@vger.kernel.org
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
> Fixes: a489043f4626 ("powerpc/pseries: Implement arch_get_random_long() based on H_RANDOM")
> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> ---
>   arch/powerpc/platforms/pseries/rng.c   | 11 ++---------
>   arch/powerpc/platforms/pseries/setup.c |  3 +++
>   2 files changed, 5 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/pseries/rng.c b/arch/powerpc/platforms/pseries/rng.c
> index 6268545947b8..d39bfce39aa1 100644
> --- a/arch/powerpc/platforms/pseries/rng.c
> +++ b/arch/powerpc/platforms/pseries/rng.c
> @@ -24,19 +24,12 @@ static int pseries_get_random_long(unsigned long *v)
>   	return 0;
>   }
>   
> -static __init int rng_init(void)
> +__init void pseries_rng_init(void)
>   {
>   	struct device_node *dn;
> -

There must be a empty line between declarations and code.

>   	dn = of_find_compatible_node(NULL, NULL, "ibm,random");
>   	if (!dn)
> -		return -ENODEV;
> -
> -	pr_info("Registering arch random hook.\n");
> -
> +		return;
>   	ppc_md.get_random_seed = pseries_get_random_long;
> -
>   	of_node_put(dn);
> -	return 0;
>   }
> -machine_subsys_initcall(pseries, rng_init);
> diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
> index afb074269b42..7f3ee2658163 100644
> --- a/arch/powerpc/platforms/pseries/setup.c
> +++ b/arch/powerpc/platforms/pseries/setup.c
> @@ -779,6 +779,8 @@ static resource_size_t pseries_pci_iov_resource_alignment(struct pci_dev *pdev,
>   }
>   #endif
>   
> +__init void pseries_rng_init(void);
> +

Prototype has to go in a header file, and should be pSeries maybe 
allthough camelCase in throw up on.

>   static void __init pSeries_setup_arch(void)
>   {
>   	set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
> @@ -839,6 +841,7 @@ static void __init pSeries_setup_arch(void)
>   	}
>   
>   	ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare;
> +	pseries_rng_init();
>   }
>   
>   static void pseries_panic(char *str)