Re: [PATCH] rockchip: board: Increase rng-seed size to make it sufficient for modern Linux

On Mon, Oct 14, 2024 at 12:10 AM Marek Vasut marex@denx.de wrote:

Let's make this override-able via environment variable, because this might be growing in the future again. Does this work ?

size_t len = env_get_ulong("kaslrseed_size", 10, 32);

Maybe `env_get_hex("rng_seed_size", 32)` would be better? As most other env are hexadecimal.

Actually it seems that entropy required to init pool early has decreased in Linux 5.19 from 64 bytes (2 * CHACHA_KEY_SIZE) to 32 bytes (BLAKE2S_HASH_SIZE) https://elixir.bootlin.com/linux/v5.18/source/drivers/char/random.c#L236 https://elixir.bootlin.com/linux/v5.19/source/drivers/char/random.c#L551 Anyway config knob should not harm.