Storing to a pointer is (effectively) atomic; no need to protect this

with splhigh(). However, the entropy-harvesting routine needs pretty
serious irq-protection, as it is called out of irq handlers etc.

Clues given by:	bde

2 files changed, 2 insertions, 10 deletions

diff --git a/sys/dev/random/harvest.c b/sys/dev/random/harvest.c
index ceb9f9f..591d0d0 100644
--- a/sys/dev/random/harvest.c
+++ b/sys/dev/random/harvest.c
@@ -47,22 +47,14 @@ static void (*reap)(struct timespec *, u_int64_t, u_int, u_int, u_int) = NULL;
 void
 random_init_harvester(void (*reaper)(struct timespec *, u_int64_t, u_int, u_int, u_int))
 {
-	intrmask_t mask;
-
-	mask = splhigh();
 	reap = reaper;
-	splx(mask);
 }
 
 /* Deinitialise the harvester at unload time */
 void
 random_deinit_harvester(void)
 {
-	intrmask_t mask;
-
-	mask = splhigh();
 	reap = NULL;
-	splx(mask);
 }
 
 /* Entropy harvesting routine. This is supposed to be fast; do */
diff --git a/sys/dev/random/yarrow.c b/sys/dev/random/yarrow.c
index 99453f6..c6ae448 100644
--- a/sys/dev/random/yarrow.c
+++ b/sys/dev/random/yarrow.c
@@ -320,8 +320,8 @@ random_harvest_internal(struct timespec *nanotime, u_int64_t entropy,
 #endif
 	if (origin < ENTROPYSOURCE) {
 
-		/* The reseed task must not be jumped on */
-		mask = splsofttq();
+		/* Called inside irq handlers; protect from interference */
+		mask = splhigh();
 
 		which = random_state.which;
 		pool = &random_state.pool[which];