From: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: pbonzini@redhat.com, rkrcmar@redhat.com, joro@8bytes.org,
vkuznets@redhat.com, rkagan@virtuozzo.com, graf@amazon.com,
jschoenh@amazon.de, karahmed@amazon.de, rimasluk@amazon.com,
jon.grimm@amd.com,
Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Subject: [PATCH v5 13/18] svm: Temporary deactivate AVIC during ExtINT handling
Date: Thu, 14 Nov 2019 14:15:15 -0600 [thread overview]
Message-ID: <1573762520-80328-14-git-send-email-suravee.suthikulpanit@amd.com> (raw)
In-Reply-To: <1573762520-80328-1-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.
Also, introduce APICV_INHIBIT_REASON_IRQWIN to be used for this reason.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/svm.c | 36 ++++++++++++++++++++++++++++++++----
2 files changed, 33 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 6c598ca..4b51222 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -852,6 +852,7 @@ enum kvm_irqchip_mode {
#define APICV_INHIBIT_REASON_DISABLE 0
#define APICV_INHIBIT_REASON_HYPERV 1
#define APICV_INHIBIT_REASON_NESTED 2
+#define APICV_INHIBIT_REASON_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 ac4901c..b7883b3 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -386,6 +386,8 @@ 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);
@@ -4450,6 +4452,15 @@ 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;
@@ -5143,6 +5154,17 @@ 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;
+
+ srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
+ kvm_request_apicv_update(vcpu->kvm, activate,
+ APICV_INHIBIT_REASON_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;
@@ -5483,9 +5505,6 @@ 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
@@ -5495,6 +5514,14 @@ 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);
}
@@ -7253,7 +7280,8 @@ static bool svm_check_apicv_inhibit_reasons(ulong bit)
{
ulong supported = BIT(APICV_INHIBIT_REASON_DISABLE) |
BIT(APICV_INHIBIT_REASON_HYPERV) |
- BIT(APICV_INHIBIT_REASON_NESTED);
+ BIT(APICV_INHIBIT_REASON_NESTED) |
+ BIT(APICV_INHIBIT_REASON_IRQWIN);
return supported & BIT(bit);
}
--
1.8.3.1
next prev parent reply other threads:[~2019-11-14 20:15 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-14 20:15 [PATCH v5 00/18] kvm: x86: Support AMD SVM AVIC w/ in-kernel irqchip mode Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 01/18] kvm: x86: Modify kvm_x86_ops.get_enable_apicv() to use struct kvm parameter Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 02/18] kvm: lapic: Introduce APICv update helper function Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 03/18] kvm: x86: Introduce APICv inhibit reason bits Suravee Suthikulpanit
2020-01-22 15:51 ` Paolo Bonzini
2019-11-14 20:15 ` [PATCH v5 04/18] kvm: x86: Add support for dynamic APICv Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 05/18] kvm: x86: Add APICv (de)activate request trace points Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 06/18] kvm: x86: svm: Add support to (de)activate posted interrupts Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 07/18] svm: Add support for setup/destroy virutal APIC backing page for AVIC Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 08/18] kvm: x86: Introduce APICv x86 ops for checking APIC inhibit reasons Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 09/18] kvm: x86: Introduce x86 ops hook for pre-update APICv Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 10/18] svm: Add support for dynamic APICv Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 11/18] kvm: x86: hyperv: Use APICv update request interface Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 12/18] svm: Deactivate AVIC when launching guest with nested SVM support Suravee Suthikulpanit
2019-11-14 20:15 ` Suravee Suthikulpanit [this message]
2020-01-22 16:32 ` [PATCH v5 13/18] svm: Temporary deactivate AVIC during ExtINT handling Paolo Bonzini
2019-11-14 20:15 ` [PATCH v5 14/18] kvm: i8254: Deactivate APICv when using in-kernel PIT re-injection mode Suravee Suthikulpanit
2020-02-18 18:51 ` Alex Williamson
2020-02-21 2:27 ` Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 15/18] kvm: lapic: Clean up APIC predefined macros Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 16/18] kvm: ioapic: Refactor kvm_ioapic_update_eoi() Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 17/18] kvm: ioapic: Lazy update IOAPIC EOI Suravee Suthikulpanit
2019-11-14 20:15 ` [PATCH v5 18/18] svm: Allow AVIC with in-kernel irqchip mode Suravee Suthikulpanit
2020-01-22 16:06 ` Paolo Bonzini
2020-01-02 10:17 ` [PATCH v5 00/18] kvm: x86: Support AMD SVM AVIC w/ " Suravee Suthikulpanit
2020-01-20 6:16 ` Suravee Suthikulpanit
2020-01-22 16:08 ` Paolo Bonzini
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1573762520-80328-14-git-send-email-suravee.suthikulpanit@amd.com \
--to=suravee.suthikulpanit@amd.com \
--cc=graf@amazon.com \
--cc=jon.grimm@amd.com \
--cc=joro@8bytes.org \
--cc=jschoenh@amazon.de \
--cc=karahmed@amazon.de \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=rimasluk@amazon.com \
--cc=rkagan@virtuozzo.com \
--cc=rkrcmar@redhat.com \
--cc=vkuznets@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).