From 49d859d78c5aeb998b6936fcb5f288f78d713489 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Sun, 31 Jul 2011 14:02:19 -0700 Subject: x86, random: Verify RDRAND functionality and allow it to be disabled If the CPU declares that RDRAND is available, go through a guranteed reseed sequence, and make sure that it is actually working (producing data.) If it does not, disable the CPU feature flag. Allow RDRAND to be disabled on the command line (as opposed to at compile time) for a user who has special requirements with regards to random numbers. Signed-off-by: H. Peter Anvin Cc: Matt Mackall Cc: Herbert Xu Cc: "Theodore Ts'o" --- arch/x86/include/asm/archrandom.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86/include/asm/archrandom.h') diff --git a/arch/x86/include/asm/archrandom.h b/arch/x86/include/asm/archrandom.h index b7b5bc02e361..0d9ec770f2f8 100644 --- a/arch/x86/include/asm/archrandom.h +++ b/arch/x86/include/asm/archrandom.h @@ -70,4 +70,6 @@ GET_RANDOM(arch_get_random_int, unsigned int, RDRAND_INT, ASM_NOP3); #endif /* CONFIG_ARCH_RANDOM */ +extern void x86_init_rdrand(struct cpuinfo_x86 *c); + #endif /* ASM_X86_ARCHRANDOM_H */ -- cgit v1.2.3