From: Andy Lutomirski <luto@xxxxxxxxxx> commit 84df7cdfbb215a34657b39f4257dab739efa2df9 upstream. There is no pool that pulls, so it was just dead code. Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx> Link: https://lore.kernel.org/r/4a05fe0c7a5c831389ef4aea51d24528ac8682c7.1577088521.git.luto@xxxxxxxxxx Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/char/random.c | 40 ---------------------------------------- 1 file changed, 40 deletions(-) --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -529,10 +529,8 @@ struct entropy_store { const struct poolinfo *poolinfo; __u32 *pool; const char *name; - struct entropy_store *pull; /* read-write data: */ - unsigned long last_pulled; spinlock_t lock; unsigned short add_ptr; unsigned short input_rotate; @@ -1368,41 +1366,6 @@ EXPORT_SYMBOL_GPL(add_disk_randomness); *********************************************************************/ /* - * This utility inline function is responsible for transferring entropy - * from the primary pool to the secondary extraction pool. We make - * sure we pull enough for a 'catastrophic reseed'. - */ -static void _xfer_secondary_pool(struct entropy_store *r, size_t nbytes); -static void xfer_secondary_pool(struct entropy_store *r, size_t nbytes) -{ - if (!r->pull || - r->entropy_count >= (nbytes << (ENTROPY_SHIFT + 3)) || - r->entropy_count > r->poolinfo->poolfracbits) - return; - - _xfer_secondary_pool(r, nbytes); -} - -static void _xfer_secondary_pool(struct entropy_store *r, size_t nbytes) -{ - __u32 tmp[OUTPUT_POOL_WORDS]; - - int bytes = nbytes; - - /* pull at least as much as a wakeup */ - bytes = max_t(int, bytes, random_read_wakeup_bits / 8); - /* but never more than the buffer size */ - bytes = min_t(int, bytes, sizeof(tmp)); - - trace_xfer_secondary_pool(r->name, bytes * 8, nbytes * 8, - ENTROPY_BITS(r), ENTROPY_BITS(r->pull)); - bytes = extract_entropy(r->pull, tmp, bytes, - random_read_wakeup_bits / 8, 0); - mix_pool_bytes(r, tmp, bytes); - credit_entropy_bits(r, bytes*8); -} - -/* * This function decides how many bytes to actually take from the * given pool, and also debits the entropy count accordingly. */ @@ -1565,7 +1528,6 @@ static ssize_t extract_entropy(struct en spin_unlock_irqrestore(&r->lock, flags); trace_extract_entropy(r->name, EXTRACT_SIZE, ENTROPY_BITS(r), _RET_IP_); - xfer_secondary_pool(r, EXTRACT_SIZE); extract_buf(r, tmp); spin_lock_irqsave(&r->lock, flags); memcpy(r->last_data, tmp, EXTRACT_SIZE); @@ -1574,7 +1536,6 @@ static ssize_t extract_entropy(struct en } trace_extract_entropy(r->name, nbytes, ENTROPY_BITS(r), _RET_IP_); - xfer_secondary_pool(r, nbytes); nbytes = account(r, nbytes, min, reserved); return _extract_entropy(r, buf, nbytes, fips_enabled); @@ -1846,7 +1807,6 @@ static void __init init_std_data(struct ktime_t now = ktime_get_real(); unsigned long rv; - r->last_pulled = jiffies; mix_pool_bytes(r, &now, sizeof(now)); for (i = r->poolinfo->poolbytes; i > 0; i -= sizeof(rv)) { if (!arch_get_random_seed_long(&rv) &&
