2019-08-15 16:41:56

by Suthikulpanit, Suravee

Subject: [PATCH v2 09/15] svm: Add support for activate/deactivate AVIC at runtime

Add necessary logics for supporting activate/deactivate AVIC at runtime.

Signed-off-by: Suravee Suthikulpanit <[email protected]>
---
arch/x86/kvm/svm.c | 27 +++++++++++++++++++++++++--
1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 47f2439..cfa4b13 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -385,6 +385,7 @@ struct amd_svm_iommu_ir {
static void svm_flush_tlb(struct kvm_vcpu *vcpu, bool invalidate_gpa);
static void svm_complete_interrupts(struct vcpu_svm *svm);
static bool svm_get_enable_apicv(struct kvm *kvm);
+static inline void avic_post_state_restore(struct kvm_vcpu *vcpu);

static int nested_svm_exit_handled(struct vcpu_svm *svm);
static int nested_svm_intercept(struct vcpu_svm *svm);
@@ -2343,6 +2344,10 @@ static void svm_vcpu_blocking(struct kvm_vcpu *vcpu)

static void svm_vcpu_unblocking(struct kvm_vcpu *vcpu)
{
+ if (kvm_check_request(KVM_REQ_APICV_ACTIVATE, vcpu))
+ kvm_vcpu_activate_apicv(vcpu);
+ if (kvm_check_request(KVM_REQ_APICV_DEACTIVATE, vcpu))
+ kvm_vcpu_deactivate_apicv(vcpu);
avic_set_running(vcpu, true);
}

@@ -5182,10 +5187,19 @@ static void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
struct vcpu_svm *svm = to_svm(vcpu);
struct vmcb *vmcb = svm->vmcb;

- if (kvm_vcpu_apicv_active(vcpu))
+ if (kvm_vcpu_apicv_active(vcpu)) {
+ /**
+ * During AVIC temporary deactivation, guest could update
+ * APIC ID, DFR and LDR registers, which would not be trapped
+ * by avic_unaccelerated_ccess_interception(). In this case,
+ * we need to check and update the AVIC logical APIC ID table
+ * accordingly before re-activating.
+ */
+ avic_post_state_restore(vcpu);
vmcb->control.int_ctl |= AVIC_ENABLE_MASK;
- else
+ } else {
vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK;
+ }
mark_dirty(vmcb, VMCB_AVIC);
}

@@ -7229,6 +7243,14 @@ static bool svm_need_emulation_on_page_fault(struct kvm_vcpu *vcpu)
return false;
}

+static void svm_pre_update_apicv_exec_ctrl(struct kvm_vcpu *vcpu, bool activate)
+{
+ if (activate)
+ avic_setup_access_page(vcpu, false);
+ else
+ avic_destroy_access_page(vcpu);
+}
+
static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
.cpu_has_kvm_support = has_svm,
.disabled_by_bios = is_disabled,
@@ -7306,6 +7328,7 @@ static bool svm_need_emulation_on_page_fault(struct kvm_vcpu *vcpu)
.set_virtual_apic_mode = svm_set_virtual_apic_mode,
.get_enable_apicv = svm_get_enable_apicv,
.refresh_apicv_exec_ctrl = svm_refresh_apicv_exec_ctrl,
+ .pre_update_apicv_exec_ctrl = svm_pre_update_apicv_exec_ctrl,
.load_eoi_exitmap = svm_load_eoi_exitmap,
.hwapic_irr_update = svm_hwapic_irr_update,
.hwapic_isr_update = svm_hwapic_isr_update,
--
1.8.3.1

2019-08-19 10:29:58

by Alexander Graf

Subject: Re: [PATCH v2 09/15] svm: Add support for activate/deactivate AVIC at runtime

On 15.08.19 18:25, Suthikulpanit, Suravee wrote:
> Add necessary logics for supporting activate/deactivate AVIC at runtime.
>
> Signed-off-by: Suravee Suthikulpanit <[email protected]>
> ---
> arch/x86/kvm/svm.c | 27 +++++++++++++++++++++++++--
> 1 file changed, 25 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 47f2439..cfa4b13 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -385,6 +385,7 @@ struct amd_svm_iommu_ir {
> static void svm_flush_tlb(struct kvm_vcpu *vcpu, bool invalidate_gpa);
> static void svm_complete_interrupts(struct vcpu_svm *svm);
> static bool svm_get_enable_apicv(struct kvm *kvm);
> +static inline void avic_post_state_restore(struct kvm_vcpu *vcpu);
>
> static int nested_svm_exit_handled(struct vcpu_svm *svm);
> static int nested_svm_intercept(struct vcpu_svm *svm);
> @@ -2343,6 +2344,10 @@ static void svm_vcpu_blocking(struct kvm_vcpu *vcpu)
>
> static void svm_vcpu_unblocking(struct kvm_vcpu *vcpu)
> {
> + if (kvm_check_request(KVM_REQ_APICV_ACTIVATE, vcpu))
> + kvm_vcpu_activate_apicv(vcpu);
> + if (kvm_check_request(KVM_REQ_APICV_DEACTIVATE, vcpu))
> + kvm_vcpu_deactivate_apicv(vcpu);
> avic_set_running(vcpu, true);
> }
>
> @@ -5182,10 +5187,19 @@ static void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
> struct vcpu_svm *svm = to_svm(vcpu);
> struct vmcb *vmcb = svm->vmcb;
>
> - if (kvm_vcpu_apicv_active(vcpu))
> + if (kvm_vcpu_apicv_active(vcpu)) {
> + /**
> + * During AVIC temporary deactivation, guest could update
> + * APIC ID, DFR and LDR registers, which would not be trapped
> + * by avic_unaccelerated_ccess_interception(). In this case,

typo

Alex