The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 77fc95f8c0dc9e1f8e620ec14d2fb65028fb7adc Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Jason@zx2c4.com Date: Tue, 7 Jun 2022 17:04:38 +0200 Subject: [PATCH] random: account for arch randomness in bits
Rather than accounting in bytes and multiplying (shifting), we can just account in bits and avoid the shift. The main motivation for this is there are other patches in flux that expand this code a bit, and avoiding the duplication of "* 8" everywhere makes things a bit clearer.
Cc: stable@vger.kernel.org Fixes: 12e45a2a6308 ("random: credit architectural init the exact amount") Signed-off-by: Jason A. Donenfeld Jason@zx2c4.com
diff --git a/drivers/char/random.c b/drivers/char/random.c index 0d6fb3eaf609..60d701a2516b 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -776,7 +776,7 @@ static struct notifier_block pm_notifier = { .notifier_call = random_pm_notifica int __init random_init(const char *command_line) { ktime_t now = ktime_get_real(); - unsigned int i, arch_bytes; + unsigned int i, arch_bits; unsigned long entropy;
#if defined(LATENT_ENTROPY_PLUGIN) @@ -784,12 +784,12 @@ int __init random_init(const char *command_line) _mix_pool_bytes(compiletime_seed, sizeof(compiletime_seed)); #endif
- for (i = 0, arch_bytes = BLAKE2S_BLOCK_SIZE; + for (i = 0, arch_bits = BLAKE2S_BLOCK_SIZE * 8; i < BLAKE2S_BLOCK_SIZE; i += sizeof(entropy)) { if (!arch_get_random_seed_long_early(&entropy) && !arch_get_random_long_early(&entropy)) { entropy = random_get_entropy(); - arch_bytes -= sizeof(entropy); + arch_bits -= sizeof(entropy) * 8; } _mix_pool_bytes(&entropy, sizeof(entropy)); } @@ -801,8 +801,8 @@ int __init random_init(const char *command_line) if (crng_ready()) crng_reseed(); else if (trust_cpu) - _credit_init_bits(arch_bytes * 8); - used_arch_random = arch_bytes * 8 >= POOL_READY_BITS; + _credit_init_bits(arch_bits); + used_arch_random = arch_bits >= POOL_READY_BITS;
WARN_ON(register_pm_notifier(&pm_notifier));