- * When the higher level interrupt code calls us with
- * interrupt disabled, we must poll the channel by calling
- * the channel callback directly when channel->target_cpu is
- * the current CPU. When the higher level interrupt code
- * calls us with interrupt enabled, let's add the
- * local_irq_save()/restore() to avoid race:
- * hv_pci_onchannelcallback() can also run in tasklet.
+ * Make sure that the ring buffer data structure doesn't get
+ * freed while we dereference the ring buffer pointer. Test
+ * for the channel's onchannel_callback being NULL within a
+ * sched_lock critical section. See also the inline comments
+ * in vmbus_reset_channel_cb().