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-rw-r--r--arch/powerpc/include/asm/archrandom.h9
-rw-r--r--arch/x86/include/asm/archrandom.h3
-rw-r--r--drivers/char/random.c3
-rw-r--r--include/linux/random.h8
4 files changed, 23 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/archrandom.h b/arch/powerpc/include/asm/archrandom.h
index 801beba4e64b..bde531103638 100644
--- a/arch/powerpc/include/asm/archrandom.h
+++ b/arch/powerpc/include/asm/archrandom.h
@@ -25,6 +25,11 @@ static inline int arch_get_random_int(unsigned int *v)
return rc;
}
+static inline int arch_has_random(void)
+{
+ return !!ppc_md.get_random_long;
+}
+
int powernv_get_random_long(unsigned long *v);
static inline int arch_get_random_seed_long(unsigned long *v)
@@ -35,6 +40,10 @@ static inline int arch_get_random_seed_int(unsigned int *v)
{
return 0;
}
+static inline int arch_has_random_seed(void)
+{
+ return 0;
+}
#endif /* CONFIG_ARCH_RANDOM */
diff --git a/arch/x86/include/asm/archrandom.h b/arch/x86/include/asm/archrandom.h
index 6ad7f6d3f97f..69f1366f1aa3 100644
--- a/arch/x86/include/asm/archrandom.h
+++ b/arch/x86/include/asm/archrandom.h
@@ -114,6 +114,9 @@ GET_SEED(arch_get_random_seed_int, unsigned int, RDSEED_INT, ASM_NOP4);
#endif /* CONFIG_X86_64 */
+#define arch_has_random() static_cpu_has(X86_FEATURE_RDRAND)
+#define arch_has_random_seed() static_cpu_has(X86_FEATURE_RDSEED)
+
#else
static inline int rdrand_long(unsigned long *v)
diff --git a/drivers/char/random.c b/drivers/char/random.c
index c35cee268e13..6b75713d953a 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1307,6 +1307,9 @@ static int arch_random_refill(void)
unsigned int i;
unsigned long buf[nlongs];
+ if (!arch_has_random_seed())
+ return 0;
+
for (i = 0; i < nlongs; i++) {
if (arch_get_random_seed_long(&buf[n]))
n++;
diff --git a/include/linux/random.h b/include/linux/random.h
index c2f08131050d..57fbbffd77a0 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -88,6 +88,10 @@ static inline int arch_get_random_int(unsigned int *v)
{
return 0;
}
+static inline int arch_has_random(void)
+{
+ return 0;
+}
static inline int arch_get_random_seed_long(unsigned long *v)
{
return 0;
@@ -96,6 +100,10 @@ static inline int arch_get_random_seed_int(unsigned int *v)
{
return 0;
}
+static inline int arch_has_random_seed(void)
+{
+ return 0;
+}
#endif
/* Pseudo random number generator from numerical recipes. */
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