From: Hyman Huang <yong.huang(a)smartx.com&gt; As advised by the GNU TLS, the caller should attempt again if the gnutls_record_{recv,send} return EAGAIN or EINTR; check the following link to view the details: https://www.gnutls.org/manual/html_node/Data-transfer-and-termination.html virNetClientSetTLSSession failed to handle EINTR/EGAIN, though EGAIN seems like it ought to be unlikely given that the caller waited for G_IO_IN. Add the {repoll, retry} logic to handle EINTR/EGAIN that may happen theoretically. This may reduce the likelihood that the upper application receives the following error message utmostly when it calls the virConnectOpenAuth API: Unable to read TLS confirmation: Resource temporarily unavailable Note that in order to fully avoid the mentioned problem, the upper application should retry virConnectOpenAuth. Signed-off-by: Hyman Huang <yong.huang(a)smartx.com&gt; --- src/rpc/virnetclient.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/src/rpc/virnetclient.c b/src/rpc/virnetclient.c index 92933220e2..ee729d5e62 100644 --- a/src/rpc/virnetclient.c +++ b/src/rpc/virnetclient.c @@ -987,6 +987,7 @@ int virNetClientSetTLSSession(virNetClient *client, * etc. If we make the grade, it will send us a '\1' byte. */ + repoll: source = virEventGLibAddSocketWatch(virNetSocketGetFD(client->sock), G_IO_IN, client->eventCtx, @@ -1003,7 +1004,14 @@ int virNetClientSetTLSSession(virNetClient *client, ignore_value(pthread_sigmask(SIG_SETMASK, &oldmask, NULL)); #endif /* !WIN32 */ + retry: len = virNetTLSSessionRead(client->tls, buf, 1); + if (len < 0 && errno == EINTR) { + goto retry; + } + if (len < 0 && errno == EAGAIN) { + goto repoll; + } if (len < 0 && errno != ENOMSG) { virReportSystemError(errno, "%s", _("Unable to read TLS confirmation")); -- 2.27.0