Merge branch 'for-next/random' into for-next/core

Avoid calling arch_get_random_seed_long() from add_interrupt_randomness()
as this can result in a firmware call on some arm64 systems.

* for-next/random:
  random: avoid arch_get_random_seed_long() when collecting IRQ randomness

1 files changed, 1 insertions, 14 deletions

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 5f3b8ac9d97b..84e24986a97a 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1261,8 +1261,6 @@ void add_interrupt_randomness(int irq, int irq_flags)
 	cycles_t		cycles = random_get_entropy();
 	__u32			c_high, j_high;
 	__u64			ip;
-	unsigned long		seed;
-	int			credit = 0;
 
 	if (cycles == 0)
 		cycles = get_reg(fast_pool, regs);
@@ -1298,23 +1296,12 @@ void add_interrupt_randomness(int irq, int irq_flags)
 
 	fast_pool->last = now;
 	__mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool));
-
-	/*
-	 * If we have architectural seed generator, produce a seed and
-	 * add it to the pool.  For the sake of paranoia don't let the
-	 * architectural seed generator dominate the input from the
-	 * interrupt noise.
-	 */
-	if (arch_get_random_seed_long(&seed)) {
-		__mix_pool_bytes(r, &seed, sizeof(seed));
-		credit = 1;
-	}
 	spin_unlock(&r->lock);
 
 	fast_pool->count = 0;
 
 	/* award one bit for the contents of the fast pool */
-	credit_entropy_bits(r, credit + 1);
+	credit_entropy_bits(r, 1);
 }
 EXPORT_SYMBOL_GPL(add_interrupt_randomness);