3 files changed, 43 insertions, 43 deletions

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 9d147d456598..b800e5479b7d 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -2016,63 +2016,65 @@ struct ctl_table random_table[] = {
 };
 #endif  /* CONFIG_SYSCTL */
 
-static u32 random_int_secret[MD5_MESSAGE_BYTES / 4] ____cacheline_aligned;
-
-int random_int_secret_init(void)
-{
-        get_random_bytes(random_int_secret, sizeof(random_int_secret));
-        return 0;
-}
-
-static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash)
-                __aligned(sizeof(unsigned long));
+struct batched_entropy {
+        union {
+                unsigned long entropy_long[CHACHA20_BLOCK_SIZE / sizeof(unsigned long)];
+                unsigned int entropy_int[CHACHA20_BLOCK_SIZE / sizeof(unsigned int)];
+        };
+        unsigned int position;
+};
 
 /*
- * Get a random word for internal kernel use only. Similar to urandom but
- * with the goal of minimal entropy pool depletion. As a result, the random
- * value is not cryptographically secure but for several uses the cost of
- * depleting entropy is too high
+ * Get a random word for internal kernel use only. The quality of the random
+ * number is either as good as RDRAND or as good as /dev/urandom, with the
+ * goal of being quite fast and not depleting entropy.
  */
-unsigned int get_random_int(void)
+static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_long);
+unsigned long get_random_long(void)
 {
-        __u32 *hash;
-        unsigned int ret;
+        unsigned long ret;
+        struct batched_entropy *batch;
 
-        if (arch_get_random_int(&ret))
+        if (arch_get_random_long(&ret))
                 return ret;
 
-        hash = get_cpu_var(get_random_int_hash);
-
-        hash[0] += current->pid + jiffies + random_get_entropy();
-        md5_transform(hash, random_int_secret);
-        ret = hash[0];
-        put_cpu_var(get_random_int_hash);
-
+        batch = &get_cpu_var(batched_entropy_long);
+        if (batch->position % ARRAY_SIZE(batch->entropy_long) == 0) {
+                extract_crng((u8 *)batch->entropy_long);
+                batch->position = 0;
+        }
+        ret = batch->entropy_long[batch->position++];
+        put_cpu_var(batched_entropy_long);
         return ret;
 }
-EXPORT_SYMBOL(get_random_int);
+EXPORT_SYMBOL(get_random_long);
 
-/*
- * Same as get_random_int(), but returns unsigned long.
- */
-unsigned long get_random_long(void)
+#if BITS_PER_LONG == 32
+unsigned int get_random_int(void)
 {
-        __u32 *hash;
-        unsigned long ret;
+        return get_random_long();
+}
+#else
+static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_int);
+unsigned int get_random_int(void)
+{
+        unsigned int ret;
+        struct batched_entropy *batch;
 
-        if (arch_get_random_long(&ret))
+        if (arch_get_random_int(&ret))
                 return ret;
 
-        hash = get_cpu_var(get_random_int_hash);
-
-        hash[0] += current->pid + jiffies + random_get_entropy();
-        md5_transform(hash, random_int_secret);
-        ret = *(unsigned long *)hash;
-        put_cpu_var(get_random_int_hash);
-
+        batch = &get_cpu_var(batched_entropy_int);
+        if (batch->position % ARRAY_SIZE(batch->entropy_int) == 0) {
+                extract_crng((u8 *)batch->entropy_int);
+                batch->position = 0;
+        }
+        ret = batch->entropy_int[batch->position++];
+        put_cpu_var(batched_entropy_int);
         return ret;
 }
-EXPORT_SYMBOL(get_random_long);
+#endif
+EXPORT_SYMBOL(get_random_int);
 
 /**
  * randomize_page - Generate a random, page aligned address
diff --git a/include/linux/random.h b/include/linux/random.h
index 7bd2403e4fef..16ab429735a7 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -37,7 +37,6 @@ extern void get_random_bytes(void *buf, int nbytes);
 extern int add_random_ready_callback(struct random_ready_callback *rdy);
 extern void del_random_ready_callback(struct random_ready_callback *rdy);
 extern void get_random_bytes_arch(void *buf, int nbytes);
-extern int random_int_secret_init(void);
 
 #ifndef MODULE
 extern const struct file_operations random_fops, urandom_fops;
diff --git a/init/main.c b/init/main.c
index b0c9d6facef9..09beb7fc6e8c 100644
--- a/init/main.c
+++ b/init/main.c
@@ -879,7 +879,6 @@ static void __init do_basic_setup(void)
         do_ctors();
         usermodehelper_enable();
         do_initcalls();
-        random_int_secret_init();
 }
 
 static void __init do_pre_smp_initcalls(void)