[v3,04/24] KVM: x86: check against irqchip_mode in pic_in_kernel()
diff mbox

Message ID 20170407085041.5257-5-david@redhat.com
State New
Headers show

Commit Message

David Hildenbrand April 7, 2017, 8:50 a.m. UTC
Let's avoid checking against kvm->arch.vpic. We have kvm->arch.irqchip_mode
for that now.

KVM_IRQCHIP_KERNEL implies a fully inititalized pic, while kvm->arch.vpic
might temporarily be set but invalidated again if e.g. kvm_ioapic_init()
fails when setting KVM_CREATE_IRQCHIP. Although current users seem to be
fine, this avoids future bugs.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
 arch/x86/kvm/irq.h | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

Patch
diff mbox

diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 59e05fe..26d8dd4 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -85,10 +85,11 @@  static inline struct kvm_pic *pic_irqchip(struct kvm *kvm)
 
 static inline int pic_in_kernel(struct kvm *kvm)
 {
-	int ret;
+	int mode = kvm->arch.irqchip_mode;
 
-	ret = (pic_irqchip(kvm) != NULL);
-	return ret;
+	/* Matches smp_wmb() when setting irqchip_mode */
+	smp_rmb();
+	return mode == KVM_IRQCHIP_KERNEL;
 }
 
 static inline int irqchip_split(struct kvm *kvm)