random: do not take pool spinlock at boot
commit afba0b80b977b2a8f16234f2acd982f82710ba33 upstream.
Since rand_initialize() is run while interrupts are still off and
nothing else is running, we don't need to repeatedly take and release
the pool spinlock, especially in the RDSEED loop.
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 2efdd5d..c8993b0 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -974,10 +974,10 @@
rv = random_get_entropy();
arch_init = false;
}
- mix_pool_bytes(&rv, sizeof(rv));
+ _mix_pool_bytes(&rv, sizeof(rv));
}
- mix_pool_bytes(&now, sizeof(now));
- mix_pool_bytes(utsname(), sizeof(*(utsname())));
+ _mix_pool_bytes(&now, sizeof(now));
+ _mix_pool_bytes(utsname(), sizeof(*(utsname())));
extract_entropy(base_crng.key, sizeof(base_crng.key));
++base_crng.generation;