Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Daniel Vacek <neelx@redhat.com>
To:     Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Tony Nguyen <anthony.l.nguyen@intel.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Richard Cochran <richardcochran@gmail.com>
Cc:     Daniel Vacek <neelx@redhat.com>, intel-wired-lan@lists.osuosl.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] ice/ptp: fix the PTP worker retrying indefinitely if the link went down
Date:   Tue, 17 Jan 2023 19:15:32 +0100
Message-Id: <20230117181533.2350335-1-neelx@redhat.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

When the link goes down the ice_ptp_tx_tstamp_work() may loop forever trying
to process the packets. In this case it makes sense to just drop them.

Signed-off-by: Daniel Vacek <neelx@redhat.com>
---
 drivers/net/ethernet/intel/ice/ice_ptp.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c b/drivers/net/ethernet/intel/ice/ice_ptp.c
index d63161d73eb16..c313177ba6676 100644
--- a/drivers/net/ethernet/intel/ice/ice_ptp.c
+++ b/drivers/net/ethernet/intel/ice/ice_ptp.c
@@ -680,6 +680,7 @@ static bool ice_ptp_tx_tstamp(struct ice_ptp_tx *tx)
 	struct ice_pf *pf;
 	struct ice_hw *hw;
 	u64 tstamp_ready;
+	bool link_up;
 	int err;
 	u8 idx;
 
@@ -695,6 +696,8 @@ static bool ice_ptp_tx_tstamp(struct ice_ptp_tx *tx)
 	if (err)
 		return false;
 
+	link_up = hw->port_info->phy.link_info.link_info & ICE_AQ_LINK_UP;
+
 	for_each_set_bit(idx, tx->in_use, tx->len) {
 		struct skb_shared_hwtstamps shhwtstamps = {};
 		u8 phy_idx = idx + tx->offset;
@@ -702,6 +705,12 @@ static bool ice_ptp_tx_tstamp(struct ice_ptp_tx *tx)
 		bool drop_ts = false;
 		struct sk_buff *skb;
 
+		/* Drop packets if the link went down */
+		if (!link_up) {
+			drop_ts = true;
+			goto skip_ts_read;
+		}
+
 		/* Drop packets which have waited for more than 2 seconds */
 		if (time_is_before_jiffies(tx->tstamps[idx].start + 2 * HZ)) {
 			drop_ts = true;
-- 
2.39.0