event_notifier: handle initialization failure better
Add 'initialized' field and use it to avoid touching event notifiers which are
either not initialized or if their initialization failed.
This is somewhat a hack, but it seems the less intrusive way to make
virtio code deal with event notifiers that failed initialization.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20201217150040.906961-4-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/util/event_notifier-posix.c b/util/event_notifier-posix.c
index 00d9320..5b2110e 100644
--- a/util/event_notifier-posix.c
+++ b/util/event_notifier-posix.c
@@ -29,6 +29,7 @@
{
e->rfd = fd;
e->wfd = fd;
+ e->initialized = true;
}
#endif
@@ -68,6 +69,7 @@
if (active) {
event_notifier_set(e);
}
+ e->initialized = true;
return 0;
fail:
@@ -78,12 +80,18 @@
void event_notifier_cleanup(EventNotifier *e)
{
+ if (!e->initialized) {
+ return;
+ }
+
if (e->rfd != e->wfd) {
close(e->rfd);
}
+
e->rfd = -1;
close(e->wfd);
e->wfd = -1;
+ e->initialized = false;
}
int event_notifier_get_fd(const EventNotifier *e)
@@ -96,6 +104,10 @@
static const uint64_t value = 1;
ssize_t ret;
+ if (!e->initialized) {
+ return -1;
+ }
+
do {
ret = write(e->wfd, &value, sizeof(value));
} while (ret < 0 && errno == EINTR);
@@ -113,6 +125,10 @@
ssize_t len;
char buffer[512];
+ if (!e->initialized) {
+ return 0;
+ }
+
/* Drain the notify pipe. For eventfd, only 8 bytes will be read. */
value = 0;
do {
