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Commit 09abb5e3 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: nVMX: call kvm_skip_emulated_instruction in nested_vmx_{fail,succeed} 



... as every invocation of nested_vmx_{fail,succeed} is immediately
followed by a call to kvm_skip_emulated_instruction().  This saves
a bit of code and eliminates some silly paths, e.g. nested_vmx_run()
ended up with a goto label purely used to call and return
kvm_skip_emulated_instruction().

Signed-off-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: default avatarJim Mattson <jmattson@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent c37a6116

arch/x86/kvm/vmx.c

+91 −154
Original line number Diff line number Diff line
@@ -8060,35 +8060,37 @@ static int handle_monitor(struct kvm_vcpu *vcpu) 


/*

 * The following 3 functions, nested_vmx_succeed()/failValid()/failInvalid(),

 * set the success or error code of an emulated VMX instruction, as specified

 * by Vol 2B, VMX Instruction Reference, "Conventions".

 * set the success or error code of an emulated VMX instruction (as specified

 * by Vol 2B, VMX Instruction Reference, "Conventions"), and skip the emulated

 * instruction.

 */

static void nested_vmx_succeed(struct kvm_vcpu *vcpu)

static int nested_vmx_succeed(struct kvm_vcpu *vcpu)

{

	vmx_set_rflags(vcpu, vmx_get_rflags(vcpu)

			& ~(X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |

			    X86_EFLAGS_ZF | X86_EFLAGS_SF | X86_EFLAGS_OF));

	return kvm_skip_emulated_instruction(vcpu);

}



static void nested_vmx_failInvalid(struct kvm_vcpu *vcpu)

static int nested_vmx_failInvalid(struct kvm_vcpu *vcpu)

{

	vmx_set_rflags(vcpu, (vmx_get_rflags(vcpu)

			& ~(X86_EFLAGS_PF | X86_EFLAGS_AF | X86_EFLAGS_ZF |

			    X86_EFLAGS_SF | X86_EFLAGS_OF))

			| X86_EFLAGS_CF);

	return kvm_skip_emulated_instruction(vcpu);

}



static void nested_vmx_failValid(struct kvm_vcpu *vcpu,

static int nested_vmx_failValid(struct kvm_vcpu *vcpu,

				u32 vm_instruction_error)

{

	if (to_vmx(vcpu)->nested.current_vmptr == -1ull) {

	/*

	 * failValid writes the error number to the current VMCS, which

		 * can't be done there isn't a current VMCS.

	 * can't be done if there isn't a current VMCS.

	 */

		nested_vmx_failInvalid(vcpu);

		return;

	}

	if (to_vmx(vcpu)->nested.current_vmptr == -1ull)

		return nested_vmx_failInvalid(vcpu);



	vmx_set_rflags(vcpu, (vmx_get_rflags(vcpu)

			& ~(X86_EFLAGS_CF | X86_EFLAGS_PF | X86_EFLAGS_AF |

			    X86_EFLAGS_SF | X86_EFLAGS_OF))
@@ -8098,6 +8100,7 @@ static void nested_vmx_failValid(struct kvm_vcpu *vcpu, 
	 * We don't need to force a shadow sync because

	 * VM_INSTRUCTION_ERROR is not shadowed

	 */

	return kvm_skip_emulated_instruction(vcpu);

}



static void nested_vmx_abort(struct kvm_vcpu *vcpu, u32 indicator)
@@ -8339,10 +8342,9 @@ static int handle_vmon(struct kvm_vcpu *vcpu) 
		return 1;

	}



	if (vmx->nested.vmxon) {

		nested_vmx_failValid(vcpu, VMXERR_VMXON_IN_VMX_ROOT_OPERATION);

		return kvm_skip_emulated_instruction(vcpu);

	}

	if (vmx->nested.vmxon)

		return nested_vmx_failValid(vcpu,

			VMXERR_VMXON_IN_VMX_ROOT_OPERATION);



	if ((vmx->msr_ia32_feature_control & VMXON_NEEDED_FEATURES)

			!= VMXON_NEEDED_FEATURES) {
@@ -8361,21 +8363,17 @@ static int handle_vmon(struct kvm_vcpu *vcpu) 
	 * Note - IA32_VMX_BASIC[48] will never be 1 for the nested case;

	 * which replaces physical address width with 32

	 */

	if (!PAGE_ALIGNED(vmptr) || (vmptr >> cpuid_maxphyaddr(vcpu))) {

		nested_vmx_failInvalid(vcpu);

		return kvm_skip_emulated_instruction(vcpu);

	}

	if (!PAGE_ALIGNED(vmptr) || (vmptr >> cpuid_maxphyaddr(vcpu)))

		return nested_vmx_failInvalid(vcpu);



	page = kvm_vcpu_gpa_to_page(vcpu, vmptr);

	if (is_error_page(page)) {

		nested_vmx_failInvalid(vcpu);

		return kvm_skip_emulated_instruction(vcpu);

	}

	if (is_error_page(page))

		return nested_vmx_failInvalid(vcpu);



	if (*(u32 *)kmap(page) != VMCS12_REVISION) {

		kunmap(page);

		kvm_release_page_clean(page);

		nested_vmx_failInvalid(vcpu);

		return kvm_skip_emulated_instruction(vcpu);

		return nested_vmx_failInvalid(vcpu);

	}

	kunmap(page);

	kvm_release_page_clean(page);
@@ -8385,8 +8383,7 @@ static int handle_vmon(struct kvm_vcpu *vcpu) 
	if (ret)

		return ret;



	nested_vmx_succeed(vcpu);

	return kvm_skip_emulated_instruction(vcpu);

	return nested_vmx_succeed(vcpu);

}



/*
@@ -8486,8 +8483,7 @@ static int handle_vmoff(struct kvm_vcpu *vcpu) 
	if (!nested_vmx_check_permission(vcpu))

		return 1;

	free_nested(to_vmx(vcpu));

	nested_vmx_succeed(vcpu);

	return kvm_skip_emulated_instruction(vcpu);

	return nested_vmx_succeed(vcpu);

}



/* Emulate the VMCLEAR instruction */
@@ -8503,15 +8499,13 @@ static int handle_vmclear(struct kvm_vcpu *vcpu) 
	if (nested_vmx_get_vmptr(vcpu, &vmptr))

		return 1;



	if (!PAGE_ALIGNED(vmptr) || (vmptr >> cpuid_maxphyaddr(vcpu))) {

		nested_vmx_failValid(vcpu, VMXERR_VMCLEAR_INVALID_ADDRESS);

		return kvm_skip_emulated_instruction(vcpu);

	}

	if (!PAGE_ALIGNED(vmptr) || (vmptr >> cpuid_maxphyaddr(vcpu)))

		return nested_vmx_failValid(vcpu,

			VMXERR_VMCLEAR_INVALID_ADDRESS);



	if (vmptr == vmx->nested.vmxon_ptr) {

		nested_vmx_failValid(vcpu, VMXERR_VMCLEAR_VMXON_POINTER);

		return kvm_skip_emulated_instruction(vcpu);

	}

	if (vmptr == vmx->nested.vmxon_ptr)

		return nested_vmx_failValid(vcpu,

			VMXERR_VMCLEAR_VMXON_POINTER);



	if (vmptr == vmx->nested.current_vmptr)

		nested_release_vmcs12(vmx);
@@ -8520,8 +8514,7 @@ static int handle_vmclear(struct kvm_vcpu *vcpu) 
			vmptr + offsetof(struct vmcs12, launch_state),

			&zero, sizeof(zero));



	nested_vmx_succeed(vcpu);

	return kvm_skip_emulated_instruction(vcpu);

	return nested_vmx_succeed(vcpu);

}



static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch);
@@ -8677,20 +8670,6 @@ static void copy_vmcs12_to_shadow(struct vcpu_vmx *vmx) 
	vmcs_load(vmx->loaded_vmcs->vmcs);

}



/*

 * VMX instructions which assume a current vmcs12 (i.e., that VMPTRLD was

 * used before) all generate the same failure when it is missing.

 */

static int nested_vmx_check_vmcs12(struct kvm_vcpu *vcpu)

{

	struct vcpu_vmx *vmx = to_vmx(vcpu);

	if (vmx->nested.current_vmptr == -1ull) {

		nested_vmx_failInvalid(vcpu);

		return 0;

	}

	return 1;

}



static int handle_vmread(struct kvm_vcpu *vcpu)

{

	unsigned long field;
@@ -8703,8 +8682,8 @@ static int handle_vmread(struct kvm_vcpu *vcpu) 
	if (!nested_vmx_check_permission(vcpu))

		return 1;



	if (!nested_vmx_check_vmcs12(vcpu))

		return kvm_skip_emulated_instruction(vcpu);

	if (to_vmx(vcpu)->nested.current_vmptr == -1ull)

		return nested_vmx_failInvalid(vcpu);



	if (!is_guest_mode(vcpu))

		vmcs12 = get_vmcs12(vcpu);
@@ -8713,20 +8692,18 @@ static int handle_vmread(struct kvm_vcpu *vcpu) 
		 * When vmcs->vmcs_link_pointer is -1ull, any VMREAD

		 * to shadowed-field sets the ALU flags for VMfailInvalid.

		 */

		if (get_vmcs12(vcpu)->vmcs_link_pointer == -1ull) {

			nested_vmx_failInvalid(vcpu);

			return kvm_skip_emulated_instruction(vcpu);

		}

		if (get_vmcs12(vcpu)->vmcs_link_pointer == -1ull)

			return nested_vmx_failInvalid(vcpu);

		vmcs12 = get_shadow_vmcs12(vcpu);

	}



	/* Decode instruction info and find the field to read */

	field = kvm_register_readl(vcpu, (((vmx_instruction_info) >> 28) & 0xf));

	/* Read the field, zero-extended to a u64 field_value */

	if (vmcs12_read_any(vmcs12, field, &field_value) < 0) {

		nested_vmx_failValid(vcpu, VMXERR_UNSUPPORTED_VMCS_COMPONENT);

		return kvm_skip_emulated_instruction(vcpu);

	}

	if (vmcs12_read_any(vmcs12, field, &field_value) < 0)

		return nested_vmx_failValid(vcpu,

			VMXERR_UNSUPPORTED_VMCS_COMPONENT);



	/*

	 * Now copy part of this value to register or memory, as requested.

	 * Note that the number of bits actually copied is 32 or 64 depending
@@ -8744,8 +8721,7 @@ static int handle_vmread(struct kvm_vcpu *vcpu) 
					    (is_long_mode(vcpu) ? 8 : 4), NULL);

	}



	nested_vmx_succeed(vcpu);

	return kvm_skip_emulated_instruction(vcpu);

	return nested_vmx_succeed(vcpu);

}
@@ -8770,8 +8746,8 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) 
	if (!nested_vmx_check_permission(vcpu))

		return 1;



	if (!nested_vmx_check_vmcs12(vcpu))

		return kvm_skip_emulated_instruction(vcpu);

	if (vmx->nested.current_vmptr == -1ull)

		return nested_vmx_failInvalid(vcpu);



	if (vmx_instruction_info & (1u << 10))

		field_value = kvm_register_readl(vcpu,
@@ -8794,11 +8770,9 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) 
	 * VMCS," then the "read-only" fields are actually read/write.

	 */

	if (vmcs_field_readonly(field) &&

	    !nested_cpu_has_vmwrite_any_field(vcpu)) {

		nested_vmx_failValid(vcpu,

	    !nested_cpu_has_vmwrite_any_field(vcpu))

		return nested_vmx_failValid(vcpu,

			VMXERR_VMWRITE_READ_ONLY_VMCS_COMPONENT);

		return kvm_skip_emulated_instruction(vcpu);

	}



	if (!is_guest_mode(vcpu))

		vmcs12 = get_vmcs12(vcpu);
@@ -8807,18 +8781,14 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) 
		 * When vmcs->vmcs_link_pointer is -1ull, any VMWRITE

		 * to shadowed-field sets the ALU flags for VMfailInvalid.

		 */

		if (get_vmcs12(vcpu)->vmcs_link_pointer == -1ull) {

			nested_vmx_failInvalid(vcpu);

			return kvm_skip_emulated_instruction(vcpu);

		}

		if (get_vmcs12(vcpu)->vmcs_link_pointer == -1ull)

			return nested_vmx_failInvalid(vcpu);

		vmcs12 = get_shadow_vmcs12(vcpu);



	}



	if (vmcs12_write_any(vmcs12, field, field_value) < 0) {

		nested_vmx_failValid(vcpu, VMXERR_UNSUPPORTED_VMCS_COMPONENT);

		return kvm_skip_emulated_instruction(vcpu);

	}

	if (vmcs12_write_any(vmcs12, field, field_value) < 0)

		return nested_vmx_failValid(vcpu,

			VMXERR_UNSUPPORTED_VMCS_COMPONENT);



	/*

	 * Do not track vmcs12 dirty-state if in guest-mode
@@ -8840,8 +8810,7 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) 
		}

	}



	nested_vmx_succeed(vcpu);

	return kvm_skip_emulated_instruction(vcpu);

	return nested_vmx_succeed(vcpu);

}



static void set_current_vmptr(struct vcpu_vmx *vmx, gpa_t vmptr)
@@ -8869,33 +8838,29 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu) 
	if (nested_vmx_get_vmptr(vcpu, &vmptr))

		return 1;



	if (!PAGE_ALIGNED(vmptr) || (vmptr >> cpuid_maxphyaddr(vcpu))) {

		nested_vmx_failValid(vcpu, VMXERR_VMPTRLD_INVALID_ADDRESS);

		return kvm_skip_emulated_instruction(vcpu);

	}

	if (!PAGE_ALIGNED(vmptr) || (vmptr >> cpuid_maxphyaddr(vcpu)))

		return nested_vmx_failValid(vcpu,

			VMXERR_VMPTRLD_INVALID_ADDRESS);



	if (vmptr == vmx->nested.vmxon_ptr) {

		nested_vmx_failValid(vcpu, VMXERR_VMPTRLD_VMXON_POINTER);

		return kvm_skip_emulated_instruction(vcpu);

	}

	if (vmptr == vmx->nested.vmxon_ptr)

		return nested_vmx_failValid(vcpu,

			VMXERR_VMPTRLD_VMXON_POINTER);



	if (vmx->nested.current_vmptr != vmptr) {

		struct vmcs12 *new_vmcs12;

		struct page *page;

		page = kvm_vcpu_gpa_to_page(vcpu, vmptr);

		if (is_error_page(page)) {

			nested_vmx_failInvalid(vcpu);

			return kvm_skip_emulated_instruction(vcpu);

		}

		if (is_error_page(page))

			return nested_vmx_failInvalid(vcpu);



		new_vmcs12 = kmap(page);

		if (new_vmcs12->hdr.revision_id != VMCS12_REVISION ||

		    (new_vmcs12->hdr.shadow_vmcs &&

		     !nested_cpu_has_vmx_shadow_vmcs(vcpu))) {

			kunmap(page);

			kvm_release_page_clean(page);

			nested_vmx_failValid(vcpu,

			return nested_vmx_failValid(vcpu,

				VMXERR_VMPTRLD_INCORRECT_VMCS_REVISION_ID);

			return kvm_skip_emulated_instruction(vcpu);

		}



		nested_release_vmcs12(vmx);
@@ -8910,8 +8875,7 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu) 
		set_current_vmptr(vmx, vmptr);

	}



	nested_vmx_succeed(vcpu);

	return kvm_skip_emulated_instruction(vcpu);

	return nested_vmx_succeed(vcpu);

}



/* Emulate the VMPTRST instruction */
@@ -8934,8 +8898,7 @@ static int handle_vmptrst(struct kvm_vcpu *vcpu) 
		kvm_inject_page_fault(vcpu, &e);

		return 1;

	}

	nested_vmx_succeed(vcpu);

	return kvm_skip_emulated_instruction(vcpu);

	return nested_vmx_succeed(vcpu);

}



/* Emulate the INVEPT instruction */
@@ -8965,11 +8928,9 @@ static int handle_invept(struct kvm_vcpu *vcpu) 


	types = (vmx->nested.msrs.ept_caps >> VMX_EPT_EXTENT_SHIFT) & 6;



	if (type >= 32 || !(types & (1 << type))) {

		nested_vmx_failValid(vcpu,

	if (type >= 32 || !(types & (1 << type)))

		return nested_vmx_failValid(vcpu,

				VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);

		return kvm_skip_emulated_instruction(vcpu);

	}



	/* According to the Intel VMX instruction reference, the memory

	 * operand is read even if it isn't needed (e.g., for type==global)
@@ -8991,14 +8952,13 @@ static int handle_invept(struct kvm_vcpu *vcpu) 
	case VMX_EPT_EXTENT_CONTEXT:

		kvm_mmu_sync_roots(vcpu);

		kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);

		nested_vmx_succeed(vcpu);

		break;

	default:

		BUG_ON(1);

		break;

	}



	return kvm_skip_emulated_instruction(vcpu);

	return nested_vmx_succeed(vcpu);

}



static u16 nested_get_vpid02(struct kvm_vcpu *vcpu)
@@ -9037,11 +8997,9 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) 
	types = (vmx->nested.msrs.vpid_caps &

			VMX_VPID_EXTENT_SUPPORTED_MASK) >> 8;



	if (type >= 32 || !(types & (1 << type))) {

		nested_vmx_failValid(vcpu,

	if (type >= 32 || !(types & (1 << type)))

		return nested_vmx_failValid(vcpu,

			VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);

		return kvm_skip_emulated_instruction(vcpu);

	}



	/* according to the intel vmx instruction reference, the memory

	 * operand is read even if it isn't needed (e.g., for type==global)
@@ -9053,21 +9011,17 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) 
		kvm_inject_page_fault(vcpu, &e);

		return 1;

	}

	if (operand.vpid >> 16) {

		nested_vmx_failValid(vcpu,

	if (operand.vpid >> 16)

		return nested_vmx_failValid(vcpu,

			VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);

		return kvm_skip_emulated_instruction(vcpu);

	}



	vpid02 = nested_get_vpid02(vcpu);

	switch (type) {

	case VMX_VPID_EXTENT_INDIVIDUAL_ADDR:

		if (!operand.vpid ||

		    is_noncanonical_address(operand.gla, vcpu)) {

			nested_vmx_failValid(vcpu,

		    is_noncanonical_address(operand.gla, vcpu))

			return nested_vmx_failValid(vcpu,

				VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);

			return kvm_skip_emulated_instruction(vcpu);

		}

		if (cpu_has_vmx_invvpid_individual_addr()) {

			__invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR,

				vpid02, operand.gla);
@@ -9076,11 +9030,9 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) 
		break;

	case VMX_VPID_EXTENT_SINGLE_CONTEXT:

	case VMX_VPID_EXTENT_SINGLE_NON_GLOBAL:

		if (!operand.vpid) {

			nested_vmx_failValid(vcpu,

		if (!operand.vpid)

			return nested_vmx_failValid(vcpu,

				VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);

			return kvm_skip_emulated_instruction(vcpu);

		}

		__vmx_flush_tlb(vcpu, vpid02, false);

		break;

	case VMX_VPID_EXTENT_ALL_CONTEXT:
@@ -9091,9 +9043,7 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) 
		return kvm_skip_emulated_instruction(vcpu);

	}



	nested_vmx_succeed(vcpu);



	return kvm_skip_emulated_instruction(vcpu);

	return nested_vmx_succeed(vcpu);

}



static int handle_invpcid(struct kvm_vcpu *vcpu)
@@ -12806,8 +12756,8 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) 
	if (!nested_vmx_check_permission(vcpu))

		return 1;



	if (!nested_vmx_check_vmcs12(vcpu))

		goto out;

	if (vmx->nested.current_vmptr == -1ull)

		return nested_vmx_failInvalid(vcpu);



	vmcs12 = get_vmcs12(vcpu);
@@ -12817,10 +12767,8 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) 
	 * rather than RFLAGS.ZF, and no error number is stored to the

	 * VM-instruction error field.

	 */

	if (vmcs12->hdr.shadow_vmcs) {

		nested_vmx_failInvalid(vcpu);

		goto out;

	}

	if (vmcs12->hdr.shadow_vmcs)

		return nested_vmx_failInvalid(vcpu);



	if (enable_shadow_vmcs)

		copy_shadow_to_vmcs12(vmx);
@@ -12835,24 +12783,18 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) 
	 * for misconfigurations which will anyway be caught by the processor

	 * when using the merged vmcs02.

	 */

	if (interrupt_shadow & KVM_X86_SHADOW_INT_MOV_SS) {

		nested_vmx_failValid(vcpu,

	if (interrupt_shadow & KVM_X86_SHADOW_INT_MOV_SS)

		return nested_vmx_failValid(vcpu,

			VMXERR_ENTRY_EVENTS_BLOCKED_BY_MOV_SS);

		goto out;

	}



	if (vmcs12->launch_state == launch) {

		nested_vmx_failValid(vcpu,

	if (vmcs12->launch_state == launch)

		return nested_vmx_failValid(vcpu,

			launch ? VMXERR_VMLAUNCH_NONCLEAR_VMCS

			       : VMXERR_VMRESUME_NONLAUNCHED_VMCS);

		goto out;

	}



	ret = check_vmentry_prereqs(vcpu, vmcs12);

	if (ret) {

		nested_vmx_failValid(vcpu, ret);

		goto out;

	}

	if (ret)

		return nested_vmx_failValid(vcpu, ret);



	/*

	 * We're finally done with prerequisite checking, and can start with
@@ -12891,9 +12833,6 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) 
		return kvm_vcpu_halt(vcpu);

	}

	return 1;



out:

	return kvm_skip_emulated_instruction(vcpu);

}



/*
@@ -13630,9 +13569,7 @@ static void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason, 
	 * flag and the VM-instruction error field of the VMCS

	 * accordingly, and skip the emulated instruction.

	 */

	nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD);



	kvm_skip_emulated_instruction(vcpu);

	(void)nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD);



	/*

	 * Restore L1's host state to KVM's software model.  We're here