int log_all)
{
int i;
+
+ if (!mem)
+ return 0;
+
for (i = 0; i < mem->nregions; ++i) {
struct vhost_memory_region *m = mem->regions + i;
unsigned long a = m->userspace_addr;
/* This actually signals the guest, using eventfd. */
void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq)
{
- __u16 flags = 0;
+ __u16 flags;
+ /* Flush out used index updates. This is paired
+ * with the barrier that the Guest executes when enabling
+ * interrupts. */
+ smp_mb();
+
if (get_user(flags, &vq->avail->flags)) {
vq_err(vq, "Failed to get flags");
return;