Commit 36be0b9d authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: x86: Add nested virtualization support for MPX 



This is simple to do, the "host" BNDCFGS is either 0 or the guest value.
However, both controls have to be present.  We cannot provide MPX if
we only have one of the "load BNDCFGS" or "clear BNDCFGS" controls.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 4ff41732

arch/x86/kvm/vmx.c

+17 −0
Original line number Diff line number Diff line
@@ -206,6 +206,7 @@ struct __packed vmcs12 { 
	u64 guest_pdptr1;

	u64 guest_pdptr2;

	u64 guest_pdptr3;

	u64 guest_bndcfgs;

	u64 host_ia32_pat;

	u64 host_ia32_efer;

	u64 host_ia32_perf_global_ctrl;
@@ -541,6 +542,7 @@ static const unsigned long shadow_read_write_fields[] = { 
	GUEST_CS_LIMIT,

	GUEST_CS_BASE,

	GUEST_ES_BASE,

	GUEST_BNDCFGS,

	CR0_GUEST_HOST_MASK,

	CR0_READ_SHADOW,

	CR4_READ_SHADOW,
@@ -596,6 +598,7 @@ static const unsigned short vmcs_field_to_offset_table[] = { 
	FIELD64(GUEST_PDPTR1, guest_pdptr1),

	FIELD64(GUEST_PDPTR2, guest_pdptr2),

	FIELD64(GUEST_PDPTR3, guest_pdptr3),

	FIELD64(GUEST_BNDCFGS, guest_bndcfgs),

	FIELD64(HOST_IA32_PAT, host_ia32_pat),

	FIELD64(HOST_IA32_EFER, host_ia32_efer),

	FIELD64(HOST_IA32_PERF_GLOBAL_CTRL, host_ia32_perf_global_ctrl),
@@ -736,6 +739,7 @@ static u32 vmx_segment_access_rights(struct kvm_segment *var); 
static void vmx_sync_pir_to_irr_dummy(struct kvm_vcpu *vcpu);

static void copy_vmcs12_to_shadow(struct vcpu_vmx *vmx);

static void copy_shadow_to_vmcs12(struct vcpu_vmx *vmx);

static bool vmx_mpx_supported(void);



static DEFINE_PER_CPU(struct vmcs *, vmxarea);

static DEFINE_PER_CPU(struct vmcs *, current_vmcs);
@@ -2287,6 +2291,8 @@ static __init void nested_vmx_setup_ctls_msrs(void) 
	nested_vmx_exit_ctls_high |= VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR |

		VM_EXIT_LOAD_IA32_EFER | VM_EXIT_SAVE_IA32_EFER |

		VM_EXIT_SAVE_VMX_PREEMPTION_TIMER;

	if (vmx_mpx_supported())

		nested_vmx_exit_ctls_high |= VM_EXIT_CLEAR_BNDCFGS;



	/* entry controls */

	rdmsr(MSR_IA32_VMX_ENTRY_CTLS,
@@ -2300,6 +2306,8 @@ static __init void nested_vmx_setup_ctls_msrs(void) 
		VM_ENTRY_LOAD_IA32_PAT;

	nested_vmx_entry_ctls_high |= (VM_ENTRY_ALWAYSON_WITHOUT_TRUE_MSR |

				       VM_ENTRY_LOAD_IA32_EFER);

	if (vmx_mpx_supported())

		nested_vmx_entry_ctls_high |= VM_ENTRY_LOAD_BNDCFGS;



	/* cpu-based controls */

	rdmsr(MSR_IA32_VMX_PROCBASED_CTLS,
@@ -7866,6 +7874,9 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) 


	set_cr4_guest_host_mask(vmx);



	if (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_BNDCFGS)

		vmcs_write64(GUEST_BNDCFGS, vmcs12->guest_bndcfgs);



	if (vmcs12->cpu_based_vm_exec_control & CPU_BASED_USE_TSC_OFFSETING)

		vmcs_write64(TSC_OFFSET,

			vmx->nested.vmcs01_tsc_offset + vmcs12->tsc_offset);
@@ -8351,6 +8362,8 @@ static void prepare_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, 
	vmcs12->guest_sysenter_cs = vmcs_read32(GUEST_SYSENTER_CS);

	vmcs12->guest_sysenter_esp = vmcs_readl(GUEST_SYSENTER_ESP);

	vmcs12->guest_sysenter_eip = vmcs_readl(GUEST_SYSENTER_EIP);

	if (vmx_mpx_supported())

		vmcs12->guest_bndcfgs = vmcs_read64(GUEST_BNDCFGS);



	/* update exit information fields: */
@@ -8460,6 +8473,10 @@ static void load_vmcs12_host_state(struct kvm_vcpu *vcpu, 
	vmcs_writel(GUEST_IDTR_BASE, vmcs12->host_idtr_base);

	vmcs_writel(GUEST_GDTR_BASE, vmcs12->host_gdtr_base);



	/* If not VM_EXIT_CLEAR_BNDCFGS, the L2 value propagates to L1.  */

	if (vmcs12->vm_exit_controls & VM_EXIT_CLEAR_BNDCFGS)

		vmcs_write64(GUEST_BNDCFGS, 0);



	if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_PAT) {

		vmcs_write64(GUEST_IA32_PAT, vmcs12->host_ia32_pat);

		vcpu->arch.pat = vmcs12->host_ia32_pat;

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