[PATCH 1/1] netdev: retry on failed ifup

[James Prestwood <prestwoj@gmail.com>]

If the interface fails to be brought up (except for RFKILL) continue
to retry. Certain wireless hardware isn't very reliable when it
comes to this code path and its been seen (on ath10k) that rarely
this call fails. It was originally thought to be tied to power save
but recently it was happening without the disable power save setting.

For headless devices its very important IWD starts up and connects
so to guard against buggy hardware continue to retry bringing the
interface up.
---
 src/netdev.c | 41 ++++++++++++++++++++++++++++++++++-------
 1 file changed, 34 insertions(+), 7 deletions(-)

diff --git a/src/netdev.c b/src/netdev.c
index 522baf7a..6f666178 100644
--- a/src/netdev.c
+++ b/src/netdev.c
@@ -139,6 +139,7 @@ struct netdev {
 	struct l_timeout *sa_query_timeout;
 	struct l_timeout *sa_query_delay;
 	struct l_timeout *group_handshake_timeout;
+	struct l_timeout *ifup_retry_timeout;
 	uint16_t sa_query_id;
 	int8_t rssi_levels[16];
 	uint8_t rssi_levels_num;
@@ -1027,6 +1028,11 @@ static void netdev_free(void *data)
 		netdev->get_link_cmd_id = 0;
 	}
 
+	if (netdev->ifup_retry_timeout) {
+		l_timeout_remove(netdev->ifup_retry_timeout);
+		netdev->ifup_retry_timeout = NULL;
+	}
+
 	scan_wdev_remove(netdev->wdev_id);
 
 	watchlist_destroy(&netdev->station_watches);
@@ -5884,6 +5890,21 @@ static bool netdev_disable_power_save(struct netdev *netdev)
 	return true;
 }
 
+static void netdev_initial_up_cb(int error, uint16_t type, const void *data,
+					uint32_t len, void *user_data);
+
+static void netdev_initial_up_retry(struct l_timeout *timeout, void *user_data)
+{
+	struct netdev *netdev = user_data;
+
+	l_timeout_remove(timeout);
+	netdev->ifup_retry_timeout = NULL;
+
+	netdev->set_powered_cmd_id =
+		l_rtnl_set_powered(rtnl, netdev->index, true,
+					netdev_initial_up_cb, netdev, NULL);
+}
+
 static void netdev_initial_up_cb(int error, uint16_t type, const void *data,
 					uint32_t len, void *user_data)
 {
@@ -5891,14 +5912,20 @@ static void netdev_initial_up_cb(int error, uint16_t type, const void *data,
 
 	netdev->set_powered_cmd_id = 0;
 
-	if (!error)
+	switch (error) {
+	case 0:
 		netdev->ifi_flags |= IFF_UP;
-	else {
-		l_error("Error bringing interface %i up: %s", netdev->index,
-			strerror(-error));
-
-		if (error != -ERFKILL)
-			return;
+		break;
+	case -ERFKILL:
+		l_error("Error bringing interface %i up due to RFKILL",
+					netdev->index);
+		break;
+	default:
+		l_error("Error bringing interface %i up: %s, retrying in 1s",
+					netdev->index, strerror(-error));
+		netdev->ifup_retry_timeout = l_timeout_create(1,
+				netdev_initial_up_retry, netdev, NULL);
+		return;
 	}
 
 	l_rtnl_set_linkmode_and_operstate(rtnl, netdev->index,
-- 
2.34.1