aboutsummaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
authorLai Jiangshan <laijs@linux.alibaba.com>2021-11-18 19:08:03 +0800
committerPaolo Bonzini <pbonzini@redhat.com>2021-12-08 04:25:06 -0500
commit15ad9762d69fd8e40a4a51828c1d6b0c1b8fbea0 (patch)
treebedb6c5f7e79779e68054a8d0425d183a67ccc07 /arch
parent3ab4ac877cfabd209d12cbd6af0aa02077bb778d (diff)
KVM: VMX: Save HOST_CR3 in vmx_prepare_switch_to_guest()
The host CR3 in the vcpu thread can only be changed when scheduling. Moving the code in vmx_prepare_switch_to_guest() makes the code simpler. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Message-Id: <20211118110814.2568-5-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/kvm/vmx/nested.c8
-rw-r--r--arch/x86/kvm/vmx/vmx.c17
2 files changed, 11 insertions, 14 deletions
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index dc5041ad860f..b03df82fc57e 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -3033,7 +3033,7 @@ static int nested_vmx_check_guest_state(struct kvm_vcpu *vcpu,
static int nested_vmx_check_vmentry_hw(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
- unsigned long cr3, cr4;
+ unsigned long cr4;
bool vm_fail;
if (!nested_early_check)
@@ -3056,12 +3056,6 @@ static int nested_vmx_check_vmentry_hw(struct kvm_vcpu *vcpu)
*/
vmcs_writel(GUEST_RFLAGS, 0);
- cr3 = __get_current_cr3_fast();
- if (unlikely(cr3 != vmx->loaded_vmcs->host_state.cr3)) {
- vmcs_writel(HOST_CR3, cr3);
- vmx->loaded_vmcs->host_state.cr3 = cr3;
- }
-
cr4 = cr4_read_shadow();
if (unlikely(cr4 != vmx->loaded_vmcs->host_state.cr4)) {
vmcs_writel(HOST_CR4, cr4);
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 73cb1322d7f1..1358770ca715 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -1103,6 +1103,7 @@ void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
#ifdef CONFIG_X86_64
int cpu = raw_smp_processor_id();
#endif
+ unsigned long cr3;
unsigned long fs_base, gs_base;
u16 fs_sel, gs_sel;
int i;
@@ -1167,6 +1168,14 @@ void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
#endif
vmx_set_host_fs_gs(host_state, fs_sel, gs_sel, fs_base, gs_base);
+
+ /* Host CR3 including its PCID is stable when guest state is loaded. */
+ cr3 = __get_current_cr3_fast();
+ if (unlikely(cr3 != host_state->cr3)) {
+ vmcs_writel(HOST_CR3, cr3);
+ host_state->cr3 = cr3;
+ }
+
vmx->guest_state_loaded = true;
}
@@ -6612,7 +6621,7 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
- unsigned long cr3, cr4;
+ unsigned long cr4;
/* Record the guest's net vcpu time for enforced NMI injections. */
if (unlikely(!enable_vnmi &&
@@ -6657,12 +6666,6 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
vmcs_writel(GUEST_RIP, vcpu->arch.regs[VCPU_REGS_RIP]);
vcpu->arch.regs_dirty = 0;
- cr3 = __get_current_cr3_fast();
- if (unlikely(cr3 != vmx->loaded_vmcs->host_state.cr3)) {
- vmcs_writel(HOST_CR3, cr3);
- vmx->loaded_vmcs->host_state.cr3 = cr3;
- }
-
cr4 = cr4_read_shadow();
if (unlikely(cr4 != vmx->loaded_vmcs->host_state.cr4)) {
vmcs_writel(HOST_CR4, cr4);