From: Andy Lutomirski <luto@kernel.org>
To: Theodore Tso <tytso@google.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
Linux API <linux-api@vger.kernel.org>,
Kees Cook <keescook@chromium.org>,
"Jason A. Donenfeld" <Jason@zx2c4.com>,
Andy Lutomirski <luto@kernel.org>
Subject: [PATCH 6/7] random: Delete code to pull data into pools
Date: Thu, 29 Aug 2019 18:11:41 -0700 [thread overview]
Message-ID: <5df8443b2987ed344e0b2e311743ace634a42d12.1567126741.git.luto@kernel.org> (raw)
In-Reply-To: <cover.1567126741.git.luto@kernel.org>
There is no pool that pulls, so it was just dead code.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
drivers/char/random.c | 40 ----------------------------------------
1 file changed, 40 deletions(-)
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 4521138231ed..99fea5cc29a8 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -528,10 +528,8 @@ 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;
@@ -1347,41 +1345,6 @@ 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.
@@ -1545,7 +1508,6 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf,
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);
@@ -1554,7 +1516,6 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf,
}
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);
@@ -1765,7 +1726,6 @@ static void __init init_std_data(struct entropy_store *r)
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) &&
--
2.21.0
next prev parent reply other threads:[~2019-08-30 1:12 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-30 1:11 [PATCH 0/7] Rework random blocking Andy Lutomirski
2019-08-30 1:11 ` [PATCH 1/7] random: Don't wake crng_init_wait when crng_init == 1 Andy Lutomirski
2019-08-30 1:11 ` [PATCH 2/7] random: Add GRND_INSECURE to return best-effort non-cryptographic bytes Andy Lutomirski
2019-08-30 1:11 ` [PATCH 3/7] random: Ignore GRND_RANDOM in getentropy(2) Andy Lutomirski
2019-08-30 1:11 ` [PATCH 4/7] random: Make /dev/random be almost like /dev/urandom Andy Lutomirski
2019-08-30 1:11 ` [PATCH 5/7] random: Remove the blocking pool Andy Lutomirski
2019-08-30 1:11 ` Andy Lutomirski [this message]
2019-08-30 1:11 ` [PATCH 7/7] random: Remove kernel.random.read_wakeup_threshold Andy Lutomirski
2019-08-30 1:49 ` [PATCH 0/7] Rework random blocking Theodore Y. Ts'o
2019-08-30 2:01 ` Andy Lutomirski
2019-09-09 9:42 ` Pavel Machek
2019-09-09 22:57 ` Andy Lutomirski
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