KVM: SVM: Implement GIF, clgi and stgi
This patch implements the GIF flag and the clgi and stgi instructions that
set this flag. Only if the flag is set (default), interrupts can be received by
the CPU.
To keep the information about that somewhere, this patch adds a new hidden
flags vector. that is used to store information that does not go into the
vmcb, but is SVM specific.
I tried to write some code to make -no-kvm-irqchip work too, but the first
level guest won't even boot with that atm, so I ditched it.
v2 moves the hflags to x86 generic code
v3 makes use of the new permission helper
v6 only enables interrupt_window if GIF=1
Acked-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 87debdc..79cc06b 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -251,7 +251,7 @@
kvm_rip_write(vcpu, svm->next_rip);
svm->vmcb->control.int_state &= ~SVM_INTERRUPT_SHADOW_MASK;
- vcpu->arch.interrupt_window_open = 1;
+ vcpu->arch.interrupt_window_open = (svm->vcpu.arch.hflags & HF_GIF_MASK);
}
static int has_svm(void)
@@ -600,6 +600,8 @@
save->cr4 = 0;
}
force_new_asid(&svm->vcpu);
+
+ svm->vcpu.arch.hflags = HF_GIF_MASK;
}
static int svm_vcpu_reset(struct kvm_vcpu *vcpu)
@@ -1234,6 +1236,36 @@
return retval;
}
+static int stgi_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
+{
+ if (nested_svm_check_permissions(svm))
+ return 1;
+
+ svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
+ skip_emulated_instruction(&svm->vcpu);
+
+ svm->vcpu.arch.hflags |= HF_GIF_MASK;
+
+ return 1;
+}
+
+static int clgi_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
+{
+ if (nested_svm_check_permissions(svm))
+ return 1;
+
+ svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
+ skip_emulated_instruction(&svm->vcpu);
+
+ svm->vcpu.arch.hflags &= ~HF_GIF_MASK;
+
+ /* After a CLGI no interrupts should come */
+ svm_clear_vintr(svm);
+ svm->vmcb->control.int_ctl &= ~V_IRQ_MASK;
+
+ return 1;
+}
+
static int invalid_op_interception(struct vcpu_svm *svm,
struct kvm_run *kvm_run)
{
@@ -1535,8 +1567,8 @@
[SVM_EXIT_VMMCALL] = vmmcall_interception,
[SVM_EXIT_VMLOAD] = invalid_op_interception,
[SVM_EXIT_VMSAVE] = invalid_op_interception,
- [SVM_EXIT_STGI] = invalid_op_interception,
- [SVM_EXIT_CLGI] = invalid_op_interception,
+ [SVM_EXIT_STGI] = stgi_interception,
+ [SVM_EXIT_CLGI] = clgi_interception,
[SVM_EXIT_SKINIT] = invalid_op_interception,
[SVM_EXIT_WBINVD] = emulate_on_interception,
[SVM_EXIT_MONITOR] = invalid_op_interception,
@@ -1684,6 +1716,9 @@
if (!kvm_cpu_has_interrupt(vcpu))
goto out;
+ if (!(svm->vcpu.arch.hflags & HF_GIF_MASK))
+ goto out;
+
if (!(vmcb->save.rflags & X86_EFLAGS_IF) ||
(vmcb->control.int_state & SVM_INTERRUPT_SHADOW_MASK) ||
(vmcb->control.event_inj & SVM_EVTINJ_VALID)) {
@@ -1710,7 +1745,8 @@
}
svm->vcpu.arch.interrupt_window_open =
- !(control->int_state & SVM_INTERRUPT_SHADOW_MASK);
+ !(control->int_state & SVM_INTERRUPT_SHADOW_MASK) &&
+ (svm->vcpu.arch.hflags & HF_GIF_MASK);
}
static void svm_do_inject_vector(struct vcpu_svm *svm)
@@ -1734,7 +1770,8 @@
svm->vcpu.arch.interrupt_window_open =
(!(control->int_state & SVM_INTERRUPT_SHADOW_MASK) &&
- (svm->vmcb->save.rflags & X86_EFLAGS_IF));
+ (svm->vmcb->save.rflags & X86_EFLAGS_IF) &&
+ (svm->vcpu.arch.hflags & HF_GIF_MASK));
if (svm->vcpu.arch.interrupt_window_open && svm->vcpu.arch.irq_summary)
/*