6.6-stable review patch. If anyone has any objections, please let me know.
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From: Sean Anderson sean.anderson@linux.dev
[ Upstream commit 6bc8a5098bf4a365c4086a4a4130bfab10a58260 ]
macb_start_xmit and macb_tx_poll can be called with bottom-halves disabled (e.g. from softirq) as well as with interrupts disabled (with netpoll). Because of this, all other functions taking tx_ptr_lock must use spin_lock_irqsave.
Fixes: 138badbc21a0 ("net: macb: use NAPI for TX completion path") Reported-by: Mike Galbraith efault@gmx.de Signed-off-by: Sean Anderson sean.anderson@linux.dev Link: https://patch.msgid.link/20250829143521.1686062-1-sean.anderson@linux.dev Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/cadence/macb_main.c | 28 ++++++++++++++---------- 1 file changed, 16 insertions(+), 12 deletions(-)
diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index 534e7f7bca4c2..b836ab2a649a2 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -1234,11 +1234,12 @@ static int macb_tx_complete(struct macb_queue *queue, int budget) { struct macb *bp = queue->bp; u16 queue_index = queue - bp->queues; + unsigned long flags; unsigned int tail; unsigned int head; int packets = 0;
- spin_lock(&queue->tx_ptr_lock); + spin_lock_irqsave(&queue->tx_ptr_lock, flags); head = queue->tx_head; for (tail = queue->tx_tail; tail != head && packets < budget; tail++) { struct macb_tx_skb *tx_skb; @@ -1297,7 +1298,7 @@ static int macb_tx_complete(struct macb_queue *queue, int budget) CIRC_CNT(queue->tx_head, queue->tx_tail, bp->tx_ring_size) <= MACB_TX_WAKEUP_THRESH(bp)) netif_wake_subqueue(bp->dev, queue_index); - spin_unlock(&queue->tx_ptr_lock); + spin_unlock_irqrestore(&queue->tx_ptr_lock, flags);
return packets; } @@ -1713,8 +1714,9 @@ static void macb_tx_restart(struct macb_queue *queue) { struct macb *bp = queue->bp; unsigned int head_idx, tbqp; + unsigned long flags;
- spin_lock(&queue->tx_ptr_lock); + spin_lock_irqsave(&queue->tx_ptr_lock, flags);
if (queue->tx_head == queue->tx_tail) goto out_tx_ptr_unlock; @@ -1726,19 +1728,20 @@ static void macb_tx_restart(struct macb_queue *queue) if (tbqp == head_idx) goto out_tx_ptr_unlock;
- spin_lock_irq(&bp->lock); + spin_lock(&bp->lock); macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(TSTART)); - spin_unlock_irq(&bp->lock); + spin_unlock(&bp->lock);
out_tx_ptr_unlock: - spin_unlock(&queue->tx_ptr_lock); + spin_unlock_irqrestore(&queue->tx_ptr_lock, flags); }
static bool macb_tx_complete_pending(struct macb_queue *queue) { bool retval = false; + unsigned long flags;
- spin_lock(&queue->tx_ptr_lock); + spin_lock_irqsave(&queue->tx_ptr_lock, flags); if (queue->tx_head != queue->tx_tail) { /* Make hw descriptor updates visible to CPU */ rmb(); @@ -1746,7 +1749,7 @@ static bool macb_tx_complete_pending(struct macb_queue *queue) if (macb_tx_desc(queue, queue->tx_tail)->ctrl & MACB_BIT(TX_USED)) retval = true; } - spin_unlock(&queue->tx_ptr_lock); + spin_unlock_irqrestore(&queue->tx_ptr_lock, flags); return retval; }
@@ -2314,6 +2317,7 @@ static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev) struct macb_queue *queue = &bp->queues[queue_index]; unsigned int desc_cnt, nr_frags, frag_size, f; unsigned int hdrlen; + unsigned long flags; bool is_lso; netdev_tx_t ret = NETDEV_TX_OK;
@@ -2374,7 +2378,7 @@ static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev) desc_cnt += DIV_ROUND_UP(frag_size, bp->max_tx_length); }
- spin_lock_bh(&queue->tx_ptr_lock); + spin_lock_irqsave(&queue->tx_ptr_lock, flags);
/* This is a hard error, log it. */ if (CIRC_SPACE(queue->tx_head, queue->tx_tail, @@ -2396,15 +2400,15 @@ static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev) wmb(); skb_tx_timestamp(skb);
- spin_lock_irq(&bp->lock); + spin_lock(&bp->lock); macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(TSTART)); - spin_unlock_irq(&bp->lock); + spin_unlock(&bp->lock);
if (CIRC_SPACE(queue->tx_head, queue->tx_tail, bp->tx_ring_size) < 1) netif_stop_subqueue(dev, queue_index);
unlock: - spin_unlock_bh(&queue->tx_ptr_lock); + spin_unlock_irqrestore(&queue->tx_ptr_lock, flags);
return ret; }