kvm: vmx: add nested virtualization support for xsaves

Add nested virtualization support for xsaves.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ad1153a..9bcc871 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -216,6 +216,7 @@ struct __packed vmcs12 {
        u64 virtual_apic_page_addr;
        u64 apic_access_addr;
        u64 ept_pointer;
+       u64 xss_exit_bitmap;
        u64 guest_physical_address;
        u64 vmcs_link_pointer;
        u64 guest_ia32_debugctl;
@@ -618,6 +619,7 @@ static const unsigned short vmcs_field_to_offset_table[] = {
        FIELD64(VIRTUAL_APIC_PAGE_ADDR, virtual_apic_page_addr),
        FIELD64(APIC_ACCESS_ADDR, apic_access_addr),
        FIELD64(EPT_POINTER, ept_pointer),
+       FIELD64(XSS_EXIT_BITMAP, xss_exit_bitmap),
        FIELD64(GUEST_PHYSICAL_ADDRESS, guest_physical_address),
        FIELD64(VMCS_LINK_POINTER, vmcs_link_pointer),
        FIELD64(GUEST_IA32_DEBUGCTL, guest_ia32_debugctl),
@@ -1104,6 +1106,12 @@ static inline int nested_cpu_has_ept(struct vmcs12 *vmcs12)
        return nested_cpu_has2(vmcs12, SECONDARY_EXEC_ENABLE_EPT);
 }
 
+static inline bool nested_cpu_has_xsaves(struct vmcs12 *vmcs12)
+{
+       return nested_cpu_has2(vmcs12, SECONDARY_EXEC_XSAVES) &&
+               vmx_xsaves_supported();
+}
+
 static inline bool is_exception(u32 intr_info)
 {
        return (intr_info & (INTR_INFO_INTR_TYPE_MASK | INTR_INFO_VALID_MASK))
@@ -2392,7 +2400,8 @@ static __init void nested_vmx_setup_ctls_msrs(void)
        nested_vmx_secondary_ctls_high &=
                SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
                SECONDARY_EXEC_UNRESTRICTED_GUEST |
-               SECONDARY_EXEC_WBINVD_EXITING;
+               SECONDARY_EXEC_WBINVD_EXITING |
+               SECONDARY_EXEC_XSAVES;
 
        if (enable_ept) {
                /* nested EPT: emulate EPT also to L1 */
@@ -7286,6 +7295,14 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
                return nested_cpu_has2(vmcs12, SECONDARY_EXEC_WBINVD_EXITING);
        case EXIT_REASON_XSETBV:
                return 1;
+       case EXIT_REASON_XSAVES: case EXIT_REASON_XRSTORS:
+               /*
+                * This should never happen, since it is not possible to
+                * set XSS to a non-zero value---neither in L1 nor in L2.
+                * If if it were, XSS would have to be checked against
+                * the XSS exit bitmap in vmcs12.
+                */
+               return nested_cpu_has2(vmcs12, SECONDARY_EXEC_XSAVES);
        default:
                return 1;
        }
@@ -8342,6 +8359,8 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
        vmcs_writel(GUEST_SYSENTER_ESP, vmcs12->guest_sysenter_esp);
        vmcs_writel(GUEST_SYSENTER_EIP, vmcs12->guest_sysenter_eip);
 
+       if (nested_cpu_has_xsaves(vmcs12))
+               vmcs_write64(XSS_EXIT_BITMAP, vmcs12->xss_exit_bitmap);
        vmcs_write64(VMCS_LINK_POINTER, -1ull);
 
        exec_control = vmcs12->pin_based_vm_exec_control;
@@ -8982,6 +9001,8 @@ static void prepare_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
        vmcs12->guest_sysenter_eip = vmcs_readl(GUEST_SYSENTER_EIP);
        if (vmx_mpx_supported())
                vmcs12->guest_bndcfgs = vmcs_read64(GUEST_BNDCFGS);
+       if (nested_cpu_has_xsaves(vmcs12))
+               vmcs12->xss_exit_bitmap = vmcs_read64(XSS_EXIT_BITMAP);
 
        /* update exit information fields: */