5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Heiner Kallweit <hkallweit1@xxxxxxxxx> [ Upstream commit 83c317d7b36bb3858cf1cb86d2635ec3f3bd6ea3 ] The only time when nr_frags isn't SKB_MAX_FRAGS is when entering rtl8169_start_xmit(). However we can use SKB_MAX_FRAGS also here because when queue isn't stopped there should always be room for MAX_SKB_FRAGS + 1 descriptors. Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx> Link: https://lore.kernel.org/r/3d1f2ad7-31d5-2cac-4f4a-394f8a3cab63@xxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Stable-dep-of: c71e3a5cffd5 ("r8169: Fix possible ring buffer corruption on fragmented Tx packets.") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/ethernet/realtek/r8169_main.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c index b678fd1436a4c..dbf885f4dd01d 100644 --- a/drivers/net/ethernet/realtek/r8169_main.c +++ b/drivers/net/ethernet/realtek/r8169_main.c @@ -4247,13 +4247,12 @@ static bool rtl8169_tso_csum_v2(struct rtl8169_private *tp, return true; } -static bool rtl_tx_slots_avail(struct rtl8169_private *tp, - unsigned int nr_frags) +static bool rtl_tx_slots_avail(struct rtl8169_private *tp) { unsigned int slots_avail = tp->dirty_tx + NUM_TX_DESC - tp->cur_tx; /* A skbuff with nr_frags needs nr_frags+1 entries in the tx queue */ - return slots_avail > nr_frags; + return slots_avail > MAX_SKB_FRAGS; } /* Versions RTL8102e and from RTL8168c onwards support csum_v2 */ @@ -4288,7 +4287,7 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, txd_first = tp->TxDescArray + entry; - if (unlikely(!rtl_tx_slots_avail(tp, frags))) { + if (unlikely(!rtl_tx_slots_avail(tp))) { if (net_ratelimit()) netdev_err(dev, "BUG! Tx Ring full when queue awake!\n"); goto err_stop_0; @@ -4333,7 +4332,7 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, WRITE_ONCE(tp->cur_tx, tp->cur_tx + frags + 1); - stop_queue = !rtl_tx_slots_avail(tp, MAX_SKB_FRAGS); + stop_queue = !rtl_tx_slots_avail(tp); if (unlikely(stop_queue)) { /* Avoid wrongly optimistic queue wake-up: rtl_tx thread must * not miss a ring update when it notices a stopped queue. @@ -4348,7 +4347,7 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, * can't. */ smp_mb__after_atomic(); - if (rtl_tx_slots_avail(tp, MAX_SKB_FRAGS)) + if (rtl_tx_slots_avail(tp)) netif_start_queue(dev); door_bell = true; } @@ -4502,10 +4501,8 @@ static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, * ring status. */ smp_store_mb(tp->dirty_tx, dirty_tx); - if (netif_queue_stopped(dev) && - rtl_tx_slots_avail(tp, MAX_SKB_FRAGS)) { + if (netif_queue_stopped(dev) && rtl_tx_slots_avail(tp)) netif_wake_queue(dev); - } /* * 8168 hack: TxPoll requests are lost when the Tx packets are * too close. Let's kick an extra TxPoll request when a burst -- 2.43.0