[PATCH 2/3] KVM: VMX: introduce alloc_loaded_vmcs

From: Paolo Bonzini
Date: Wed Jan 31 2018 - 16:09:42 EST


Group together the calls to alloc_vmcs and loaded_vmcs_init. Soon we'll also
allocate an MSR bitmap there.

Cc: stable@xxxxxxxxxxxxxxx # prereq for Spectre mitigation
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/vmx.c | 36 ++++++++++++++++++++++--------------
1 file changed, 22 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ad6a883b7a32..ab4b9bc99a52 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3829,11 +3829,6 @@ static struct vmcs *alloc_vmcs_cpu(int cpu)
return vmcs;
}

-static struct vmcs *alloc_vmcs(void)
-{
- return alloc_vmcs_cpu(raw_smp_processor_id());
-}
-
static void free_vmcs(struct vmcs *vmcs)
{
free_pages((unsigned long)vmcs, vmcs_config.order);
@@ -3852,6 +3847,22 @@ static void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
WARN_ON(loaded_vmcs->shadow_vmcs != NULL);
}

+static struct vmcs *alloc_vmcs(void)
+{
+ return alloc_vmcs_cpu(raw_smp_processor_id());
+}
+
+static int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
+{
+ loaded_vmcs->vmcs = alloc_vmcs();
+ if (!loaded_vmcs->vmcs)
+ return -ENOMEM;
+
+ loaded_vmcs->shadow_vmcs = NULL;
+ loaded_vmcs_init(loaded_vmcs);
+ return 0;
+}
+
static void free_kvm_area(void)
{
int cpu;
@@ -7145,12 +7156,11 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct vmcs *shadow_vmcs;
+ int r;

- vmx->nested.vmcs02.vmcs = alloc_vmcs();
- vmx->nested.vmcs02.shadow_vmcs = NULL;
- if (!vmx->nested.vmcs02.vmcs)
+ r = alloc_loaded_vmcs(&vmx->nested.vmcs02);
+ if (r < 0)
goto out_vmcs02;
- loaded_vmcs_init(&vmx->nested.vmcs02);

if (cpu_has_vmx_msr_bitmap()) {
vmx->nested.msr_bitmap =
@@ -9545,13 +9555,11 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
if (!vmx->guest_msrs)
goto free_pml;

- vmx->loaded_vmcs = &vmx->vmcs01;
- vmx->loaded_vmcs->vmcs = alloc_vmcs();
- vmx->loaded_vmcs->shadow_vmcs = NULL;
- if (!vmx->loaded_vmcs->vmcs)
+ err = alloc_loaded_vmcs(&vmx->vmcs01);
+ if (err < 0)
goto free_msrs;
- loaded_vmcs_init(vmx->loaded_vmcs);

+ vmx->loaded_vmcs = &vmx->vmcs01;
cpu = get_cpu();
vmx_vcpu_load(&vmx->vcpu, cpu);
vmx->vcpu.cpu = cpu;
--
2.14.3