Commit 15ad9762 authored by Lai Jiangshan's avatar Lai Jiangshan Committed by Paolo Bonzini
Browse files

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: default avatarLai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211118110814.2568-5-jiangshanlai@gmail.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 3ab4ac87

arch/x86/kvm/vmx/nested.c

+1 −7
Original line number Diff line number Diff line
@@ -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);

arch/x86/kvm/vmx/vmx.c

+10 −7
Original line number Diff line number Diff line
@@ -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);