Commit 945ee35e authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: Mask KVM_GET_SUPPORTED_CPUID data with Linux cpuid info 



This allows Linux to mask cpuid bits if, for example, nx is enabled on only
some cpus.

Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 2a6b20b8

arch/x86/kvm/x86.c

+9 −0
Original line number Diff line number Diff line
@@ -2227,6 +2227,11 @@ static int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu, 
	return r;

}



static void cpuid_mask(u32 *word, int wordnum)

{

	*word &= boot_cpu_data.x86_capability[wordnum];

}



static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,

			   u32 index)

{
@@ -2301,7 +2306,9 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, 
		break;

	case 1:

		entry->edx &= kvm_supported_word0_x86_features;

		cpuid_mask(&entry->edx, 0);

		entry->ecx &= kvm_supported_word4_x86_features;

		cpuid_mask(&entry->ecx, 4);

		/* we support x2apic emulation even if host does not support

		 * it since we emulate x2apic in software */

		entry->ecx |= F(X2APIC);
@@ -2392,7 +2399,9 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, 
		break;

	case 0x80000001:

		entry->edx &= kvm_supported_word1_x86_features;

		cpuid_mask(&entry->edx, 1);

		entry->ecx &= kvm_supported_word6_x86_features;

		cpuid_mask(&entry->ecx, 6);

		break;

	}