From: "Suthikulpanit, Suravee" <Suravee.Suthikulpanit@amd.com>
To: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>
Cc: "pbonzini@redhat.com" <pbonzini@redhat.com>,
"rkrcmar@redhat.com" <rkrcmar@redhat.com>,
"joro@8bytes.org" <joro@8bytes.org>,
"vkuznets@redhat.com" <vkuznets@redhat.com>,
"rkagan@virtuozzo.com" <rkagan@virtuozzo.com>,
"graf@amazon.com" <graf@amazon.com>,
"jschoenh@amazon.de" <jschoenh@amazon.de>,
"karahmed@amazon.de" <karahmed@amazon.de>,
"rimasluk@amazon.com" <rimasluk@amazon.com>,
"Grimm, Jon" <Jon.Grimm@amd.com>,
"Suthikulpanit, Suravee" <Suravee.Suthikulpanit@amd.com>
Subject: [PATCH v4 12/17] svm: Temporary deactivate AVIC during ExtINT handling
Date: Fri, 1 Nov 2019 22:41:36 +0000 [thread overview]
Message-ID: <1572648072-84536-13-git-send-email-suravee.suthikulpanit@amd.com> (raw)
In-Reply-To: <1572648072-84536-1-git-send-email-suravee.suthikulpanit@amd.com>
AMD AVIC does not support ExtINT. Therefore, AVIC must be temporary
deactivated and fall back to using legacy interrupt injection via vINTR
and interrupt window.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/svm.c | 37 ++++++++++++++++++++++++++++++++++---
2 files changed, 35 insertions(+), 3 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 55d6476..fe61269 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -857,6 +857,7 @@ enum kvm_irqchip_mode {
#define APICV_DEACT_BIT_DISABLE 0
#define APICV_DEACT_BIT_HYPERV 1
#define APICV_DEACT_BIT_NESTED 2
+#define APICV_DEACT_BIT_IRQWIN 3
struct kvm_arch {
unsigned long n_used_mmu_pages;
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 7f59b1a..0e7ff04 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -388,6 +388,8 @@ struct amd_svm_iommu_ir {
static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
static void svm_flush_tlb(struct kvm_vcpu *vcpu, bool invalidate_gpa);
static void svm_complete_interrupts(struct vcpu_svm *svm);
+static void svm_request_update_avic(struct kvm_vcpu *vcpu, bool activate);
+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);
@@ -4479,6 +4481,15 @@ static int interrupt_window_interception(struct vcpu_svm *svm)
{
kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);
svm_clear_vintr(svm);
+
+ /*
+ * For AVIC, the only reason to end up here is ExtINTs.
+ * In this case AVIC was temporarily disabled for
+ * requesting the IRQ window and we have to re-enable it.
+ */
+ if (svm_get_enable_apicv(svm->vcpu.kvm))
+ svm_request_update_avic(&svm->vcpu, true);
+
svm->vmcb->control.int_ctl &= ~V_IRQ_MASK;
mark_dirty(svm->vmcb, VMCB_INTR);
++svm->vcpu.stat.irq_window_exits;
@@ -5166,6 +5177,21 @@ static void svm_hwapic_isr_update(struct kvm_vcpu *vcpu, int max_isr)
{
}
+static void svm_request_update_avic(struct kvm_vcpu *vcpu, bool activate)
+{
+ if (!lapic_in_kernel(vcpu))
+ return;
+ /*
+ * kvm_request_apicv_update() expects a prior read unlock
+ * on the the kvm->srcu since it subsequently calls read lock
+ * and re-unlock in __x86_set_memory_region()
+ * when updating APIC_ACCESS_PAGE_PRIVATE_MEMSLOT.
+ */
+ srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
+ kvm_request_apicv_update(vcpu->kvm, activate, APICV_DEACT_BIT_IRQWIN);
+ vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
+}
+
static int svm_set_pi_irte_mode(struct kvm_vcpu *vcpu, bool activate)
{
int ret = 0;
@@ -5504,9 +5530,6 @@ static void enable_irq_window(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
- if (kvm_vcpu_apicv_active(vcpu))
- return;
-
/*
* In case GIF=0 we can't rely on the CPU to tell us when GIF becomes
* 1, because that's a separate STGI/VMRUN intercept. The next time we
@@ -5516,6 +5539,14 @@ static void enable_irq_window(struct kvm_vcpu *vcpu)
* window under the assumption that the hardware will set the GIF.
*/
if ((vgif_enabled(svm) || gif_set(svm)) && nested_svm_intr(svm)) {
+ /*
+ * IRQ window is not needed when AVIC is enabled,
+ * unless we have pending ExtINT since it cannot be injected
+ * via AVIC. In such case, we need to temporarily disable AVIC,
+ * and fallback to injecting IRQ via V_IRQ.
+ */
+ if (kvm_vcpu_apicv_active(vcpu))
+ svm_request_update_avic(vcpu, false);
svm_set_vintr(svm);
svm_inject_irq(svm, 0x0);
}
--
1.8.3.1
next prev parent reply other threads:[~2019-11-01 22:41 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-01 22:41 [PATCH v4 00/17] kvm: x86: Support AMD SVM AVIC w/ in-kernel irqchip mode Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 01/17] kvm: x86: Modify kvm_x86_ops.get_enable_apicv() to use struct kvm parameter Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 02/17] kvm: lapic: Introduce APICv update helper function Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 03/17] kvm: x86: Introduce APICv deactivate bits Suthikulpanit, Suravee
2019-11-02 9:51 ` Paolo Bonzini
2019-11-01 22:41 ` [PATCH v4 04/17] kvm: x86: Add support for activate/de-activate APICv at runtime Suthikulpanit, Suravee
2019-11-02 9:52 ` Paolo Bonzini
2019-11-04 19:22 ` Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 05/17] kvm: x86: Add APICv activate/deactivate request trace points Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 06/17] kvm: x86: svm: Add support to activate/deactivate posted interrupts Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 07/17] svm: Add support for setup/destroy virutal APIC backing page for AVIC Suthikulpanit, Suravee
2019-11-04 21:53 ` Roman Kagan
2019-11-12 0:05 ` Suravee Suthikulpanit
2019-11-01 22:41 ` [PATCH v4 08/17] kvm: x86: Introduce APICv pre-update hook Suthikulpanit, Suravee
2019-11-04 22:05 ` Roman Kagan
2019-11-12 0:08 ` Suravee Suthikulpanit
2019-11-12 11:12 ` Roman Kagan
2019-11-01 22:41 ` [PATCH v4 09/17] svm: Add support for activate/deactivate AVIC at runtime Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 10/17] kvm: x86: hyperv: Use APICv update request interface Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 11/17] svm: Deactivate AVIC when launching guest with nested SVM support Suthikulpanit, Suravee
2019-11-01 22:41 ` Suthikulpanit, Suravee [this message]
2019-11-02 10:01 ` [PATCH v4 12/17] svm: Temporary deactivate AVIC during ExtINT handling Paolo Bonzini
2019-11-01 22:41 ` [PATCH v4 13/17] kvm: i8254: Deactivate APICv when using in-kernel PIT re-injection mode Suthikulpanit, Suravee
2019-11-02 9:57 ` Paolo Bonzini
2019-11-04 18:54 ` Suthikulpanit, Suravee
2019-11-04 21:49 ` Paolo Bonzini
2019-11-05 7:05 ` Graf (AWS), Alexander
2019-11-05 8:40 ` Roman Kagan
2019-11-04 23:17 ` Roman Kagan
2019-11-05 22:47 ` Paolo Bonzini
2019-11-11 17:37 ` Suravee Suthikulpanit
2019-11-12 12:22 ` Roman Kagan
2019-11-01 22:41 ` [PATCH v4 14/17] kvm: lapic: Clean up APIC predefined macros Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 15/17] kvm: ioapic: Refactor kvm_ioapic_update_eoi() Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 16/17] kvm: ioapic: Lazy update IOAPIC EOI Suthikulpanit, Suravee
2019-11-01 22:41 ` [PATCH v4 17/17] svm: Allow AVIC with in-kernel irqchip mode Suthikulpanit, Suravee
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