Module Name: src
Committed By: tls
Date: Mon Aug 26 23:41:24 UTC 2013
Modified Files:
src/sys/dev: rnd_private.h
src/sys/kern: kern_rndq.c kern_rndsink.c
Log Message:
Temporary fix for previous: avoid recursion through rnd_wakeup_readers()
when entropy first becomes available.
To generate a diff of this commit:
cvs rdiff -u -r1.2 -r1.3 src/sys/dev/rnd_private.h
cvs rdiff -u -r1.15 -r1.16 src/sys/kern/kern_rndq.c
cvs rdiff -u -r1.3 -r1.4 src/sys/kern/kern_rndsink.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/rnd_private.h
diff -u src/sys/dev/rnd_private.h:1.2 src/sys/dev/rnd_private.h:1.3
--- src/sys/dev/rnd_private.h:1.2 Sun Aug 25 21:12:56 2013
+++ src/sys/dev/rnd_private.h Mon Aug 26 23:41:24 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: rnd_private.h,v 1.2 2013/08/25 21:12:56 tls Exp $ */
+/* $NetBSD: rnd_private.h,v 1.3 2013/08/26 23:41:24 tls Exp $ */
/*-
* Copyright (c) 1997 The NetBSD Foundation, Inc.
@@ -55,6 +55,7 @@
(short read ok) */
uint32_t rnd_extract_data(void *, uint32_t, uint32_t);
-void rnd_process_events(void); /* XXX should be static */
+int rnd_process_events(void); /* XXX should be static */
+void rnd_wakeup_readers(void); /* XXX should be static */
#endif
Index: src/sys/kern/kern_rndq.c
diff -u src/sys/kern/kern_rndq.c:1.15 src/sys/kern/kern_rndq.c:1.16
--- src/sys/kern/kern_rndq.c:1.15 Sun Aug 25 21:12:56 2013
+++ src/sys/kern/kern_rndq.c Mon Aug 26 23:41:24 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_rndq.c,v 1.15 2013/08/25 21:12:56 tls Exp $ */
+/* $NetBSD: kern_rndq.c,v 1.16 2013/08/26 23:41:24 tls Exp $ */
/*-
* Copyright (c) 1997-2013 The NetBSD Foundation, Inc.
@@ -32,7 +32,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_rndq.c,v 1.15 2013/08/25 21:12:56 tls Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_rndq.c,v 1.16 2013/08/26 23:41:24 tls Exp $");
#include <sys/param.h>
#include <sys/ioctl.h>
@@ -141,7 +141,6 @@ static krndsource_t rnd_source_no_collec
void *rnd_process, *rnd_wakeup;
struct callout skew_callout;
-void rnd_wakeup_readers(void);
static inline u_int32_t rnd_estimate_entropy(krndsource_t *, u_int32_t);
static inline u_int32_t rnd_counter(void);
static void rnd_intr(void *);
@@ -169,7 +168,7 @@ rnd_init_softint(void) {
rnd_intr, NULL);
rnd_wakeup = softint_establish(SOFTINT_CLOCK|SOFTINT_MPSAFE,
rnd_wake, NULL);
- rnd_process_events();
+ rnd_intr(NULL);
}
/*
@@ -816,8 +815,10 @@ rnd_hwrng_test(rnd_sample_t *sample)
* by the add routines directly if the callout has never fired (that
* is, if we are "cold" -- just booted).
*
+ * Returns >0 if we got enough entropy to distribute some (wake sleepers)
+ * 0 elsewise.
*/
-void
+int
rnd_process_events(void)
{
rnd_sample_t *sample = NULL;
@@ -931,19 +932,15 @@ rnd_process_events(void)
rnd_sample_free(sample);
}
-
- /*
- * Wake up any potential readers waiting.
- */
- if (wake) {
- rnd_schedule_wakeup();
- }
+ return wake;
}
static void
rnd_intr(void *arg)
{
- rnd_process_events();
+ if (rnd_process_events()) {
+ rnd_schedule_wakeup();
+ }
}
static void
@@ -1031,13 +1028,19 @@ rnd_extract_data_locked(void *p, u_int32
u_int32_t
rnd_extract_data(void *p, u_int32_t len, u_int32_t flags)
{
+ int wake;
uint32_t retval;
- rnd_process_events(); /* XXX extra take/release rndpool_mtx */
+ wake = rnd_process_events(); /* XXX extra take/release rndpool_mtx */
mutex_spin_enter(&rndpool_mtx);
retval = rnd_extract_data_locked(p, len, flags);
mutex_spin_exit(&rndpool_mtx);
+
+ if (wake) {
+ rnd_wakeup_readers();
+ }
+
return retval;
}
Index: src/sys/kern/kern_rndsink.c
diff -u src/sys/kern/kern_rndsink.c:1.3 src/sys/kern/kern_rndsink.c:1.4
--- src/sys/kern/kern_rndsink.c:1.3 Sun Aug 25 21:12:56 2013
+++ src/sys/kern/kern_rndsink.c Mon Aug 26 23:41:24 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_rndsink.c,v 1.3 2013/08/25 21:12:56 tls Exp $ */
+/* $NetBSD: kern_rndsink.c,v 1.4 2013/08/26 23:41:24 tls Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_rndsink.c,v 1.3 2013/08/25 21:12:56 tls Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_rndsink.c,v 1.4 2013/08/26 23:41:24 tls Exp $");
#include <sys/param.h>
#include <sys/types.h>
@@ -131,7 +131,7 @@ rndpool_maybe_extract(void *buffer, size
const uint32_t bits_needed = ((bytes + RND_ENTROPY_THRESHOLD) * NBBY);
- rnd_process_events(); /* XXX extra take/release rndpool_mtx */
+ (void)rnd_process_events(); /* XXX extra take/release rndpool_mtx */
mutex_spin_enter(&rndpool_mtx);
if (bits_needed <= rndpool_get_entropy_count(&rnd_pool)) {
