[libvirt] [PATCH] qemu: Try multiple times to open unix monitor socket

Unlike the pty monitor (which we know exists since we scrape its path from stdout), we have no way of knowing that the unix monitor socket should exist/ be initialized. As a result, some of my KVM guests randomly fail to start on F10 host. Try to open the unix socket in a 3 second timeout loop. Ignore EACCES (path does not exist if a first time run) and ECONNREFUSED (leftover socket from a previous run hasn't been removed yet). Fixes things for me. --- src/qemu_driver.c | 22 +++++++++++++++++++++- 1 files changed, 21 insertions(+), 1 deletions(-) diff --git a/src/qemu_driver.c b/src/qemu_driver.c index e2b7acb..200718b 100644 --- a/src/qemu_driver.c +++ b/src/qemu_driver.c @@ -874,6 +874,8 @@ qemudOpenMonitorUnix(virConnectPtr conn, { struct sockaddr_un addr; int monfd; + int timeout = 3; /* In seconds */ + int ret, i; if ((monfd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { virReportSystemError(conn, errno, @@ -885,10 +887,28 @@ qemudOpenMonitorUnix(virConnectPtr conn, addr.sun_family = AF_UNIX; strncpy(addr.sun_path, monitor, sizeof(addr.sun_path)); - if (connect(monfd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { + do { + ret = connect(monfd, (struct sockaddr *) &addr, sizeof(addr)); + + if (ret == 0) + break; + + if (errno == EACCES || errno == ECONNREFUSED) { + /* EACCES : Socket may not have shown up yet + * ECONNREFUSED : Leftover socket hasn't been removed yet */ + continue; + } + virReportSystemError(conn, errno, "%s", _("failed to connect to monitor socket")); goto error; + + } while ((++i <= timeout*5) && (usleep(.2 * 1000000) <= 0)); + + if (ret != 0) { + virReportSystemError(conn, errno, "%s", + _("monitor socket did not show up.")); + goto error; } if (qemudOpenMonitorCommon(conn, driver, vm, monfd, reconnect) < 0) -- 1.6.0.6