From: Nitesh Narayan Lal <nitesh@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
seanjc@google.com, w90p710@gmail.com, pbonzini@redhat.com,
vkuznets@redhat.com, nitesh@redhat.com
Subject: [PATCH] Revert "KVM: x86: Unconditionally enable irqs in guest context"
Date: Tue, 5 Jan 2021 14:28:44 -0500 [thread overview]
Message-ID: <20210105192844.296277-1-nitesh@redhat.com> (raw)
This reverts commit d7a08882a0a4b4e176691331ee3f492996579534.
After the introduction of the patch:
87fa7f3e9: x86/kvm: Move context tracking where it belongs
since we have moved guest_exit_irqoff closer to the VM-Exit, explicit
enabling of irqs to process pending interrupts should not be required
within vcpu_enter_guest anymore.
Conflicts:
arch/x86/kvm/svm.c
Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com>
---
arch/x86/kvm/svm/svm.c | 9 +++++++++
arch/x86/kvm/x86.c | 11 -----------
2 files changed, 9 insertions(+), 11 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index cce0143a6f80..c9b2fbb32484 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4187,6 +4187,15 @@ static int svm_check_intercept(struct kvm_vcpu *vcpu,
static void svm_handle_exit_irqoff(struct kvm_vcpu *vcpu)
{
+ kvm_before_interrupt(vcpu);
+ local_irq_enable();
+ /*
+ * We must have an instruction with interrupts enabled, so
+ * the timer interrupt isn't delayed by the interrupt shadow.
+ */
+ asm("nop");
+ local_irq_disable();
+ kvm_after_interrupt(vcpu);
}
static void svm_sched_in(struct kvm_vcpu *vcpu, int cpu)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3f7c1fc7a3ce..3e17c9ffcad8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9023,18 +9023,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
kvm_x86_ops.handle_exit_irqoff(vcpu);
- /*
- * Consume any pending interrupts, including the possible source of
- * VM-Exit on SVM and any ticks that occur between VM-Exit and now.
- * An instruction is required after local_irq_enable() to fully unblock
- * interrupts on processors that implement an interrupt shadow, the
- * stat.exits increment will do nicely.
- */
- kvm_before_interrupt(vcpu);
- local_irq_enable();
++vcpu->stat.exits;
- local_irq_disable();
- kvm_after_interrupt(vcpu);
if (lapic_in_kernel(vcpu)) {
s64 delta = vcpu->arch.apic->lapic_timer.advance_expire_delta;
--
2.27.0
next reply other threads:[~2021-01-05 19:30 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-05 19:28 Nitesh Narayan Lal [this message]
2021-01-06 0:42 ` [PATCH] Revert "KVM: x86: Unconditionally enable irqs in guest context" Wanpeng Li
2021-01-06 0:47 ` Sean Christopherson
2021-01-06 1:35 ` Nitesh Narayan Lal
2021-01-15 3:20 ` Wanpeng Li
2021-01-19 1:27 ` Wanpeng Li
2021-01-06 10:09 ` Vitaly Kuznetsov
2021-01-06 17:11 ` Sean Christopherson
2021-01-07 9:33 ` Vitaly Kuznetsov
2021-01-07 9:41 ` Wanpeng Li
2021-01-12 21:43 ` Nitesh Narayan Lal
2021-01-12 22:04 ` Sean Christopherson
2021-01-07 10:55 ` Xinlong Lin
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