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-rw-r--r--lib/Kconfig.kgdb11
-rw-r--r--lib/random32.c48
-rw-r--r--lib/ratelimit.c3
-rw-r--r--lib/smp_processor_id.c5
4 files changed, 37 insertions, 30 deletions
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index 2cfd2721f7ed..9b5d1d7f2ef7 100644
--- a/lib/Kconfig.kgdb
+++ b/lib/Kconfig.kgdb
@@ -4,14 +4,17 @@ config HAVE_ARCH_KGDB
menuconfig KGDB
bool "KGDB: kernel debugging with remote gdb"
- select FRAME_POINTER
depends on HAVE_ARCH_KGDB
depends on DEBUG_KERNEL && EXPERIMENTAL
help
If you say Y here, it will be possible to remotely debug the
- kernel using gdb. Documentation of kernel debugger is available
- at http://kgdb.sourceforge.net as well as in DocBook form
- in Documentation/DocBook/. If unsure, say N.
+ kernel using gdb. It is recommended but not required, that
+ you also turn on the kernel config option
+ CONFIG_FRAME_POINTER to aid in producing more reliable stack
+ backtraces in the external debugger. Documentation of
+ kernel debugger is available at http://kgdb.sourceforge.net
+ as well as in DocBook form in Documentation/DocBook/. If
+ unsure, say N.
if KGDB
diff --git a/lib/random32.c b/lib/random32.c
index ca87d86992bd..217d5c4b666d 100644
--- a/lib/random32.c
+++ b/lib/random32.c
@@ -56,23 +56,12 @@ static u32 __random32(struct rnd_state *state)
return (state->s1 ^ state->s2 ^ state->s3);
}
-static void __set_random32(struct rnd_state *state, unsigned long s)
+/*
+ * Handle minimum values for seeds
+ */
+static inline u32 __seed(u32 x, u32 m)
{
- if (s == 0)
- s = 1; /* default seed is 1 */
-
-#define LCG(n) (69069 * n)
- state->s1 = LCG(s);
- state->s2 = LCG(state->s1);
- state->s3 = LCG(state->s2);
-
- /* "warm it up" */
- __random32(state);
- __random32(state);
- __random32(state);
- __random32(state);
- __random32(state);
- __random32(state);
+ return (x < m) ? x + m : x;
}
/**
@@ -107,7 +96,7 @@ void srandom32(u32 entropy)
*/
for_each_possible_cpu (i) {
struct rnd_state *state = &per_cpu(net_rand_state, i);
- __set_random32(state, state->s1 ^ entropy);
+ state->s1 = __seed(state->s1 ^ entropy, 1);
}
}
EXPORT_SYMBOL(srandom32);
@@ -122,7 +111,19 @@ static int __init random32_init(void)
for_each_possible_cpu(i) {
struct rnd_state *state = &per_cpu(net_rand_state,i);
- __set_random32(state, i + jiffies);
+
+#define LCG(x) ((x) * 69069) /* super-duper LCG */
+ state->s1 = __seed(LCG(i + jiffies), 1);
+ state->s2 = __seed(LCG(state->s1), 7);
+ state->s3 = __seed(LCG(state->s2), 15);
+
+ /* "warm it up" */
+ __random32(state);
+ __random32(state);
+ __random32(state);
+ __random32(state);
+ __random32(state);
+ __random32(state);
}
return 0;
}
@@ -135,13 +136,18 @@ core_initcall(random32_init);
static int __init random32_reseed(void)
{
int i;
- unsigned long seed;
for_each_possible_cpu(i) {
struct rnd_state *state = &per_cpu(net_rand_state,i);
+ u32 seeds[3];
+
+ get_random_bytes(&seeds, sizeof(seeds));
+ state->s1 = __seed(seeds[0], 1);
+ state->s2 = __seed(seeds[1], 7);
+ state->s3 = __seed(seeds[2], 15);
- get_random_bytes(&seed, sizeof(seed));
- __set_random32(state, seed);
+ /* mix it in */
+ __random32(state);
}
return 0;
}
diff --git a/lib/ratelimit.c b/lib/ratelimit.c
index 35136671b215..26187edcc7ea 100644
--- a/lib/ratelimit.c
+++ b/lib/ratelimit.c
@@ -15,7 +15,6 @@
#include <linux/module.h>
static DEFINE_SPINLOCK(ratelimit_lock);
-static unsigned long flags;
/*
* __ratelimit - rate limiting
@@ -26,6 +25,8 @@ static unsigned long flags;
*/
int __ratelimit(struct ratelimit_state *rs)
{
+ unsigned long flags;
+
if (!rs->interval)
return 1;
diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c
index c4381d9516f6..0f8fc22ed103 100644
--- a/lib/smp_processor_id.c
+++ b/lib/smp_processor_id.c
@@ -11,7 +11,6 @@ notrace unsigned int debug_smp_processor_id(void)
{
unsigned long preempt_count = preempt_count();
int this_cpu = raw_smp_processor_id();
- cpumask_of_cpu_ptr_declare(this_mask);
if (likely(preempt_count))
goto out;
@@ -23,9 +22,7 @@ notrace unsigned int debug_smp_processor_id(void)
* Kernel threads bound to a single CPU can safely use
* smp_processor_id():
*/
- cpumask_of_cpu_ptr_next(this_mask, this_cpu);
-
- if (cpus_equal(current->cpus_allowed, *this_mask))
+ if (cpus_equal(current->cpus_allowed, cpumask_of_cpu(this_cpu)))
goto out;
/*