From c447e76b4cabb49ddae8e49c5758f031f35d55fb Mon Sep 17 00:00:00 2001 From: Liang Li Date: Thu, 21 May 2015 04:41:25 +0800 Subject: kvm/fpu: Enable eager restore kvm FPU for MPX The MPX feature requires eager KVM FPU restore support. We have verified that MPX cannot work correctly with the current lazy KVM FPU restore mechanism. Eager KVM FPU restore should be enabled if the MPX feature is exposed to VM. Signed-off-by: Yang Zhang Signed-off-by: Liang Li [Also activate the FPU on AMD processors. - Paolo] Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/x86/kvm/cpuid.c') diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 59b69f6a2844..1d08ad3582d0 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -16,6 +16,8 @@ #include #include #include +#include /* For use_eager_fpu. Ugh! */ +#include /* For use_eager_fpu. Ugh! */ #include #include #include "cpuid.h" @@ -95,6 +97,8 @@ int kvm_update_cpuid(struct kvm_vcpu *vcpu) if (best && (best->eax & (F(XSAVES) | F(XSAVEC)))) best->ebx = xstate_required_size(vcpu->arch.xcr0, true); + vcpu->arch.eager_fpu = guest_cpuid_has_mpx(vcpu); + /* * The existing code assumes virtual address is 48-bit in the canonical * address checks; exit if it is ever changed. -- cgit v1.2.3