[PATCH 4.14 055/237] random: remove dead code left over from blocking pool

From: Greg Kroah-Hartman
Date: Thu Jun 23 2022 - 13:30:20 EST


From: Eric Biggers <ebiggers@xxxxxxxxxx>

commit 118a4417e14348b2e46f5e467da8444ec4757a45 upstream.

Remove some dead code that was left over following commit 90ea1c6436d2
("random: remove the blocking pool").

Cc: linux-crypto@xxxxxxxxxxxxxxx
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Theodore Ts'o <tytso@xxxxxxx>
Reviewed-by: Andy Lutomirski <luto@xxxxxxxxxx>
Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/char/random.c | 17 +-------
include/trace/events/random.h | 83 ------------------------------------------
2 files changed, 3 insertions(+), 97 deletions(-)

--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -502,7 +502,6 @@ struct entropy_store {
unsigned short add_ptr;
unsigned short input_rotate;
int entropy_count;
- unsigned int initialized:1;
unsigned int last_data_init:1;
__u8 last_data[EXTRACT_SIZE];
};
@@ -662,7 +661,7 @@ static void process_random_ready_list(vo
*/
static void credit_entropy_bits(struct entropy_store *r, int nbits)
{
- int entropy_count, orig, has_initialized = 0;
+ int entropy_count, orig;
const int pool_size = r->poolinfo->poolfracbits;
int nfrac = nbits << ENTROPY_SHIFT;

@@ -719,23 +718,14 @@ retry:
if (cmpxchg(&r->entropy_count, orig, entropy_count) != orig)
goto retry;

- if (has_initialized) {
- r->initialized = 1;
- kill_fasync(&fasync, SIGIO, POLL_IN);
- }
-
trace_credit_entropy_bits(r->name, nbits,
entropy_count >> ENTROPY_SHIFT, _RET_IP_);

if (r == &input_pool) {
int entropy_bits = entropy_count >> ENTROPY_SHIFT;

- if (crng_init < 2) {
- if (entropy_bits < 128)
- return;
+ if (crng_init < 2 && entropy_bits >= 128)
crng_reseed(&primary_crng, r);
- entropy_bits = ENTROPY_BITS(r);
- }
}
}

@@ -1390,8 +1380,7 @@ retry:
}

/*
- * This function does the actual extraction for extract_entropy and
- * extract_entropy_user.
+ * This function does the actual extraction for extract_entropy.
*
* Note: we assume that .poolwords is a multiple of 16 words.
*/
--- a/include/trace/events/random.h
+++ b/include/trace/events/random.h
@@ -85,28 +85,6 @@ TRACE_EVENT(credit_entropy_bits,
__entry->entropy_count, (void *)__entry->IP)
);

-TRACE_EVENT(push_to_pool,
- TP_PROTO(const char *pool_name, int pool_bits, int input_bits),
-
- TP_ARGS(pool_name, pool_bits, input_bits),
-
- TP_STRUCT__entry(
- __field( const char *, pool_name )
- __field( int, pool_bits )
- __field( int, input_bits )
- ),
-
- TP_fast_assign(
- __entry->pool_name = pool_name;
- __entry->pool_bits = pool_bits;
- __entry->input_bits = input_bits;
- ),
-
- TP_printk("%s: pool_bits %d input_pool_bits %d",
- __entry->pool_name, __entry->pool_bits,
- __entry->input_bits)
-);
-
TRACE_EVENT(debit_entropy,
TP_PROTO(const char *pool_name, int debit_bits),

@@ -161,35 +139,6 @@ TRACE_EVENT(add_disk_randomness,
MINOR(__entry->dev), __entry->input_bits)
);

-TRACE_EVENT(xfer_secondary_pool,
- TP_PROTO(const char *pool_name, int xfer_bits, int request_bits,
- int pool_entropy, int input_entropy),
-
- TP_ARGS(pool_name, xfer_bits, request_bits, pool_entropy,
- input_entropy),
-
- TP_STRUCT__entry(
- __field( const char *, pool_name )
- __field( int, xfer_bits )
- __field( int, request_bits )
- __field( int, pool_entropy )
- __field( int, input_entropy )
- ),
-
- TP_fast_assign(
- __entry->pool_name = pool_name;
- __entry->xfer_bits = xfer_bits;
- __entry->request_bits = request_bits;
- __entry->pool_entropy = pool_entropy;
- __entry->input_entropy = input_entropy;
- ),
-
- TP_printk("pool %s xfer_bits %d request_bits %d pool_entropy %d "
- "input_entropy %d", __entry->pool_name, __entry->xfer_bits,
- __entry->request_bits, __entry->pool_entropy,
- __entry->input_entropy)
-);
-
DECLARE_EVENT_CLASS(random__get_random_bytes,
TP_PROTO(int nbytes, unsigned long IP),

@@ -253,38 +202,6 @@ DEFINE_EVENT(random__extract_entropy, ex
TP_ARGS(pool_name, nbytes, entropy_count, IP)
);

-DEFINE_EVENT(random__extract_entropy, extract_entropy_user,
- TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
- unsigned long IP),
-
- TP_ARGS(pool_name, nbytes, entropy_count, IP)
-);
-
-TRACE_EVENT(random_read,
- TP_PROTO(int got_bits, int need_bits, int pool_left, int input_left),
-
- TP_ARGS(got_bits, need_bits, pool_left, input_left),
-
- TP_STRUCT__entry(
- __field( int, got_bits )
- __field( int, need_bits )
- __field( int, pool_left )
- __field( int, input_left )
- ),
-
- TP_fast_assign(
- __entry->got_bits = got_bits;
- __entry->need_bits = need_bits;
- __entry->pool_left = pool_left;
- __entry->input_left = input_left;
- ),
-
- TP_printk("got_bits %d still_needed_bits %d "
- "blocking_pool_entropy_left %d input_entropy_left %d",
- __entry->got_bits, __entry->got_bits, __entry->pool_left,
- __entry->input_left)
-);
-
TRACE_EVENT(urandom_read,
TP_PROTO(int got_bits, int pool_left, int input_left),