KVM: x86: Propagate fpu_alloc errors

Memory allocation may fail. Propagate such errors.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -624,7 +624,7 @@ int kvm_pic_set_irq(void *opaque, int irq, int level);
 
 void kvm_inject_nmi(struct kvm_vcpu *vcpu);
 
-void fx_init(struct kvm_vcpu *vcpu);
+int fx_init(struct kvm_vcpu *vcpu);
 
 void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu);
 void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,

arch/x86/kvm/svm.c

@@ -904,13 +904,18 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
 	svm->asid_generation = 0;
 	init_vmcb(svm);
 
-	fx_init(&svm->vcpu);
+	err = fx_init(&svm->vcpu);
+	if (err)
+		goto free_page4;
+
 	svm->vcpu.arch.apic_base = 0xfee00000 | MSR_IA32_APICBASE_ENABLE;
 	if (kvm_vcpu_is_bsp(&svm->vcpu))
 		svm->vcpu.arch.apic_base |= MSR_IA32_APICBASE_BSP;
 
 	return &svm->vcpu;
 
+free_page4:
+	__free_page(hsave_page);
 free_page3:
 	__free_pages(nested_msrpm_pages, MSRPM_ALLOC_ORDER);
 free_page2:

arch/x86/kvm/vmx.c

@@ -2659,7 +2659,9 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
 		msr |= MSR_IA32_APICBASE_BSP;
 	kvm_set_apic_base(&vmx->vcpu, msr);
 
-	fx_init(&vmx->vcpu);
+	ret = fx_init(&vmx->vcpu);
+	if (ret != 0)
+		goto out;
 
 	seg_setup(VCPU_SREG_CS);
 	/*

arch/x86/kvm/x86.c

@@ -5114,12 +5114,19 @@ int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 	return 0;
 }
 
-void fx_init(struct kvm_vcpu *vcpu)
+int fx_init(struct kvm_vcpu *vcpu)
 {
-	fpu_alloc(&vcpu->arch.guest_fpu);
+	int err;
+
+	err = fpu_alloc(&vcpu->arch.guest_fpu);
+	if (err)
+		return err;
+
 	fpu_finit(&vcpu->arch.guest_fpu);
 
 	vcpu->arch.cr0 |= X86_CR0_ET;
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(fx_init);