virtio-rng is both too complicated and insufficient for initial rng seeding. It's far too complicated to use for KASLR or any other early boot random number needs. It also provides /dev/random-style bits, which means that making guest boot wait for virtio-rng is unacceptably slow, and doing it asynchronously means that /dev/urandom might be predictable when userspace starts. This introduces a very simple synchronous mechanism to get /dev/urandom-style bits. This is a KVM change: am I supposed to write a unit test somewhere? Andy Lutomirski (4): x86,kvm: Add MSR_KVM_GET_RNG_SEED and a matching feature bit random,x86: Add arch_get_slow_rng_u64 random: Seed pools from arch_get_slow_rng_u64 at startup x86,kaslr: Use MSR_KVM_GET_RNG_SEED for KASLR if available Documentation/virtual/kvm/cpuid.txt | 3 +++ arch/x86/Kconfig | 4 ++++ arch/x86/boot/compressed/aslr.c | 27 +++++++++++++++++++++++++++ arch/x86/include/asm/archslowrng.h | 30 ++++++++++++++++++++++++++++++ arch/x86/include/uapi/asm/kvm_para.h | 2 ++ arch/x86/kernel/kvm.c | 22 ++++++++++++++++++++++ arch/x86/kvm/cpuid.c | 3 ++- arch/x86/kvm/x86.c | 4 ++++ drivers/char/random.c | 14 +++++++++++++- include/linux/random.h | 9 +++++++++ 10 files changed, 116 insertions(+), 2 deletions(-) create mode 100644 arch/x86/include/asm/archslowrng.h -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
