When Tx IRQs are used, txq_bufs_free() can be called from both the Tx path and from NAPI poll(). This led to CPU stalls as if these two tasks (Tx and Poll) are scheduled on two CPUs at the same time, DMA unmapping operations are done on the same txq buffers.
This patch adds a check not to call txq_done() from the Tx path if Tx interrupts are used as it does not make sense to do so. Fixes: edc660fa09e2 ("net: mvpp2: replace TX coalescing interrupts with hrtimer") Signed-off-by: Antoine Tenart <antoine.ten...@free-electrons.com> --- drivers/net/ethernet/marvell/mvpp2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c index 037f26dfe31c..60b4f3d995af 100644 --- a/drivers/net/ethernet/marvell/mvpp2.c +++ b/drivers/net/ethernet/marvell/mvpp2.c @@ -6499,7 +6499,7 @@ static int mvpp2_tx(struct sk_buff *skb, struct net_device *dev) } /* Finalize TX processing */ - if (txq_pcpu->count >= txq->done_pkts_coal) + if (!port->has_tx_irqs && txq_pcpu->count >= txq->done_pkts_coal) mvpp2_txq_done(port, txq, txq_pcpu); /* Set the timer in case not all frags were processed */ -- 2.14.2