From de32ef6d79ddd3f4975e54a2e998e23bce8432d4 Mon Sep 17 00:00:00 2001
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: Tue, 12 Oct 2021 14:40:37 +0300
Subject: [PATCH] net: mscc: ocelot: warn when a PTP IRQ is raised for an unknown skb
Git-commit: 9fde506e0c53b8309f69b18b4b8144c544b4b3b1
Patch-mainline: v5.15-rc6
References: stable-5.14.14
commit 9fde506e0c53b8309f69b18b4b8144c544b4b3b1 upstream.
When skb_match is NULL, it means we received a PTP IRQ for a timestamp
ID that the kernel has no idea about, since there is no skb in the
timestamping queue with that timestamp ID.
This is a grave error and not something to just "continue" over.
So print a big warning in case this happens.
Also, move the check above ocelot_get_hwtimestamp(), there is no point
in reading the full 64-bit current PTP time if we're not going to do
anything with it anyway for this skb.
Fixes: 4e3b0468e6d7 ("net: mscc: PTP Hardware Clock (PHC) support")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/ethernet/mscc/ocelot.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index 87ac24a7e003..6e172f40d6bb 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -714,12 +714,12 @@ void ocelot_get_txtstamp(struct ocelot *ocelot)
spin_unlock_irqrestore(&port->tx_skbs.lock, flags);
+ if (WARN_ON(!skb_match))
+ continue;
+
/* Get the h/w timestamp */
ocelot_get_hwtimestamp(ocelot, &ts);
- if (unlikely(!skb_match))
- continue;
-
/* Set the timestamp into the skb */
memset(&shhwtstamps, 0, sizeof(shhwtstamps));
shhwtstamps.hwtstamp = ktime_set(ts.tv_sec, ts.tv_nsec);
--
2.26.2