@@ -2871,10 +2871,25 @@ static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
const struct kvm_io_range *r2)
{
- if (r1->addr < r2->addr)
+ gpa_t addr1 = r1->addr;
+ gpa_t addr2 = r2->addr;
+
+ if (addr1 < addr2)
return -1;
- if (r1->addr + r1->len > r2->addr + r2->len)
+
+ /* If r2->len == 0, match the exact address. If r2->len != 0,
+ * accept any overlapping write. Any order is acceptable for
+ * overlapping ranges, because kvm_io_bus_get_first_dev ensures
+ * we process all of them.
+ */
+ if (r2->len) {
+ addr1 += r1->len;
+ addr2 += r2->len;
+ }
+
+ if (addr1 > addr2)
return 1;
+
return 0;
}