Modern Linux requires 32 byte seed to initialize random pool, but u-boot currently provides only 8 bytes. Increase rng-seed size to make Linux happy and initialize rng pool instantly.
Boot with 8 byte rng-seed: # dmesg | grep crng [ 12.089286] random: crng init done Boot with 32 byte rng-seed: # dmesg | grep crng [ 0.000000] random: crng init done
https://github.com/torvalds/linux/blob/7234e2ea0edd00bfb6bb2159e55878c19885c...
Signed-off-by: Alex Shumsky alexthreed@gmail.com Fixes: d2048bafae40 ("rockchip: board: Add board_rng_seed() for all Rockchip devices") ---
Changes in v2: - add env config knob rng_seed_size - 12-character commit SHA in Fixes
arch/arm/mach-rockchip/board.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/arch/arm/mach-rockchip/board.c b/arch/arm/mach-rockchip/board.c index 3fadf7e412..f9f0d7214c 100644 --- a/arch/arm/mach-rockchip/board.c +++ b/arch/arm/mach-rockchip/board.c @@ -472,9 +472,15 @@ __weak int misc_init_r(void) __weak int board_rng_seed(struct abuf *buf) { struct udevice *dev; - size_t len = 0x8; + ulong len = env_get_ulong("rng_seed_size", 10, 32); u64 *data;
+ if (len < 32) { + // rng_seed_size should be 32 bytes for Linux 5.19+, or 64 for older Linux'es + log_warning("Too small rng_seed_size (%lu). It is likely insufficient to init linux crng\n", + len); + } + data = malloc(len); if (!data) { printf("Out of memory\n");