From 4fe6d78b2e241f41208dfb07605aace4becfc747 Mon Sep 17 00:00:00 2001 From: Gal Hammer Date: Sun, 14 Jan 2018 12:06:55 +0200 Subject: [PATCH] virtio: postpone the execution of event_notifier_cleanup function Use the EventNotifier's cleanup callback function to execute the event_notifier_cleanup function after kvm unregistered the eventfd. This change supports running the virtio_bus_set_host_notifier function inside a memory region transaction. Otherwise, a closed fd is sent to kvm, which results in a failure. Signed-off-by: Gal Hammer Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- accel/kvm/kvm-all.c | 4 ++++ hw/virtio/virtio-bus.c | 19 +++++++++++-------- 2 files changed, 15 insertions(+), 8 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index f290f487a5..071f4f57c0 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -812,6 +812,10 @@ static void kvm_mem_ioeventfd_del(MemoryListener *listener, if (r < 0) { abort(); } + + if (e->cleanup) { + e->cleanup(e); + } } static void kvm_io_ioeventfd_add(MemoryListener *listener, diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c index 3042232daf..8106346927 100644 --- a/hw/virtio/virtio-bus.c +++ b/hw/virtio/virtio-bus.c @@ -256,6 +256,15 @@ bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus) return k->ioeventfd_assign && k->ioeventfd_enabled(proxy); } +static void virtio_bus_cleanup_event_notifier(EventNotifier *notifier) +{ + /* Test and clear notifier after disabling event, + * in case poll callback didn't have time to run. + */ + virtio_queue_host_notifier_read(notifier); + event_notifier_cleanup(notifier); +} + /* * This function switches ioeventfd on/off in the device. * The caller must set or clear the handlers for the EventNotifier. @@ -283,19 +292,13 @@ int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign) r = k->ioeventfd_assign(proxy, notifier, n, true); if (r < 0) { error_report("%s: unable to assign ioeventfd: %d", __func__, r); - goto cleanup_event_notifier; + virtio_bus_cleanup_event_notifier(notifier); } - return 0; } else { + notifier->cleanup = virtio_bus_cleanup_event_notifier; k->ioeventfd_assign(proxy, notifier, n, false); } -cleanup_event_notifier: - /* Test and clear notifier after disabling event, - * in case poll callback didn't have time to run. - */ - virtio_queue_host_notifier_read(notifier); - event_notifier_cleanup(notifier); return r; } -- GitLab