From man poll(2), poll does not set errno=EAGAIN, however it does set errno=EINTR. Have libvirt retry on the appropriate errno.
Under heavy load, a program of mine kept getting libvirt errors 'poll on socket failed: Interrupted system call'. The signals were SIGCHLD from processes forked by threads unrelated to those using libvirt. diff --git a/src/rpc/virnetclient.c b/src/rpc/virnetclient.c index 2530ffa..f2a6922 100644 --- a/src/rpc/virnetclient.c +++ b/src/rpc/virnetclient.c @@ -1374,7 +1374,7 @@ static int virNetClientIOEventLoop(virNetClientPtr client, repoll: ret = poll(fds, ARRAY_CARDINALITY(fds), timeout); - if (ret < 0 && errno == EAGAIN) + if (ret < 0 && errno == EINTR) goto repoll; ignore_value(pthread_sigmask(SIG_SETMASK, &oldmask, NULL));