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-rw-r--r--lib/Kconfig.kgdb11
-rw-r--r--lib/iommu-helper.c8
-rw-r--r--lib/random32.c48
3 files changed, 34 insertions, 33 deletions
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index 2cfd2721f7e..9b5d1d7f2ef 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/iommu-helper.c b/lib/iommu-helper.c
index 889ddce2021..a3b8d4c3f77 100644
--- a/lib/iommu-helper.c
+++ b/lib/iommu-helper.c
@@ -80,11 +80,3 @@ void iommu_area_free(unsigned long *map, unsigned long start, unsigned int nr)
}
}
EXPORT_SYMBOL(iommu_area_free);
-
-unsigned long iommu_num_pages(unsigned long addr, unsigned long len)
-{
- unsigned long size = roundup((addr & ~PAGE_MASK) + len, PAGE_SIZE);
-
- return size >> PAGE_SHIFT;
-}
-EXPORT_SYMBOL(iommu_num_pages);
diff --git a/lib/random32.c b/lib/random32.c
index ca87d86992b..217d5c4b666 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;
}