[Qemu-devel] [PATCH] vfio-pci: Add missing kvm_enabled() checks

[Stefan Hajnoczi <stefanha@redhat.com>]

It's necessary to check kvm_enabled() since a QEMU binary can be
compiled with KVM support but TCG can be used at run-time.
kvm_check_extension() segfaults if kvm_state is NULL.

Reported-by: Joe Terranova <joeterranova@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 hw/vfio_pci.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/hw/vfio_pci.c b/hw/vfio_pci.c
index fbfe670..677dc48 100644
--- a/hw/vfio_pci.c
+++ b/hw/vfio_pci.c
@@ -275,7 +275,8 @@ static void vfio_enable_intx_kvm(VFIODevice *vdev)
     int ret, argsz;
     int32_t *pfd;
 
-    if (!kvm_irqfds_enabled() ||
+    if (!kvm_enabled() ||
+        !kvm_irqfds_enabled() ||
         vdev->intx.route.mode != PCI_INTX_ENABLED ||
         !kvm_check_extension(kvm_state, KVM_CAP_IRQFD_RESAMPLE)) {
         return;
@@ -438,7 +439,8 @@ static int vfio_enable_intx(VFIODevice *vdev)
      * Only conditional to avoid generating error messages on platforms
      * where we won't actually use the result anyway.
      */
-    if (kvm_irqfds_enabled() &&
+    if (kvm_enabled() &&
+        kvm_irqfds_enabled() &&
         kvm_check_extension(kvm_state, KVM_CAP_IRQFD_RESAMPLE)) {
         vdev->intx.route = pci_device_route_intx_to_irq(&vdev->pdev,
                                                         vdev->intx.pin);
-- 
1.8.0.2