Am 24.01.24 um 18:38 schrieb Hanna Czenczek: > During drain, we do not care about virtqueue notifications, which is why > we remove the handlers on it. When removing those handlers, whether vq > notifications are enabled or not depends on whether we were in polling > mode or not; if not, they are enabled (by default); if so, they have > been disabled by the io_poll_start callback. > > Because we do not care about those notifications after removing the > handlers, this is fine. However, we have to explicitly ensure they are > enabled when re-attaching the handlers, so we will resume receiving > notifications. We do this in virtio_queue_aio_attach_host_notifier*(). > If such a function is called while we are in a polling section, > attaching the notifiers will then invoke the io_poll_start callback, > re-disabling notifications. > > Because we will always miss virtqueue updates in the drained section, we > also need to poll the virtqueue once after attaching the notifiers. > > Buglink: https://issues.redhat.com/browse/RHEL-3934 > Signed-off-by: Hanna Czenczek <hre...@redhat.com>
Tested-by: Fiona Ebner <f.eb...@proxmox.com> Reviewed-by: Fiona Ebner <f.eb...@proxmox.com>
