Il 24/02/2014 11:58, Liu, Jinsong ha scritto:
@@ -599,6 +599,9 @@ int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) u64 old_xcr0 = vcpu->arch.xcr0; u64 valid_bits; + if (!kvm_x86_ops->mpx_supported || !kvm_x86_ops->mpx_supported()) + xcr0 &= ~(XSTATE_BNDREGS | XSTATE_BNDCSR); + /* Only support XCR_XFEATURE_ENABLED_MASK(xcr0) now */ if (index != XCR_XFEATURE_ENABLED_MASK) return 1;
This hunk is incorrect, and I can simply drop it when applying. If MPX is not supported, it should not be in the 0Dh CPUID leaf and thus in vcpu->arch.guest_supported_xcr0.
This however relies on userspace passing a "sensible" value of CPUID. I'll send a patch to strengthen the computation of guest_supported_xcr0.
Thanks! Paolo -- 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
