From: "Jason A. Donenfeld" Jason@zx2c4.com
commit a96cfe2d427064325ecbf56df8816c6b871ec285 upstream.
Rather than sometimes checking `crng_init < 2`, we should always use the crng_ready() macro, so that should we change anything later, it's consistent. Additionally, that macro already has a likely() around it, which means we don't need to open code our own likely() and unlikely() annotations.
Cc: Theodore Ts'o tytso@mit.edu Reviewed-by: Dominik Brodowski linux@dominikbrodowski.net Signed-off-by: Jason A. Donenfeld Jason@zx2c4.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/char/random.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-)
--- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -125,18 +125,13 @@ static void try_to_generate_entropy(void */ int wait_for_random_bytes(void) { - if (likely(crng_ready())) - return 0; - - do { + while (!crng_ready()) { int ret; ret = wait_event_interruptible_timeout(crng_init_wait, crng_ready(), HZ); if (ret) return ret > 0 ? 0 : ret; - try_to_generate_entropy(); - } while (!crng_ready()); - + } return 0; } EXPORT_SYMBOL(wait_for_random_bytes); @@ -291,7 +286,7 @@ static void crng_reseed(void) ++next_gen; WRITE_ONCE(base_crng.generation, next_gen); WRITE_ONCE(base_crng.birth, jiffies); - if (crng_init < 2) { + if (!crng_ready()) { crng_init = 2; finalize_init = true; } @@ -359,7 +354,7 @@ static void crng_make_state(u32 chacha_s * ready, we do fast key erasure with the base_crng directly, because * this is what crng_pre_init_inject() mutates during early init. */ - if (unlikely(!crng_ready())) { + if (!crng_ready()) { bool ready;
spin_lock_irqsave(&base_crng.lock, flags); @@ -802,7 +797,7 @@ static void credit_entropy_bits(size_t n entropy_count = min_t(unsigned int, POOL_BITS, orig + add); } while (cmpxchg(&input_pool.entropy_count, orig, entropy_count) != orig);
- if (crng_init < 2 && entropy_count >= POOL_MIN_BITS) + if (!crng_ready() && entropy_count >= POOL_MIN_BITS) crng_reseed(); }
@@ -959,7 +954,7 @@ int __init rand_initialize(void) extract_entropy(base_crng.key, sizeof(base_crng.key)); ++base_crng.generation;
- if (arch_init && trust_cpu && crng_init < 2) { + if (arch_init && trust_cpu && !crng_ready()) { crng_init = 2; pr_notice("crng init done (trusting CPU's manufacturer)\n"); } @@ -1548,7 +1543,7 @@ static long random_ioctl(struct file *f, case RNDRESEEDCRNG: if (!capable(CAP_SYS_ADMIN)) return -EPERM; - if (crng_init < 2) + if (!crng_ready()) return -ENODATA; crng_reseed(); return 0;