From f2386cf7c5f4ff5d7b584f5d92014edd7df6c676 Mon Sep 17 00:00:00 2001 From: Aleksander Jan Bajkowski Date: Tue, 8 Jun 2021 23:21:07 +0200 Subject: net: lantiq: disable interrupt before sheduling NAPI This patch fixes TX hangs with threaded NAPI enabled. The scheduled NAPI seems to be executed in parallel with the interrupt on second thread. Sometimes it happens that ltq_dma_disable_irq() is executed after xrx200_tx_housekeeping(). The symptom is that TX interrupts are disabled in the DMA controller. As a result, the TX hangs after a few seconds of the iperf test. Scheduling NAPI after disabling interrupts fixes this issue. Tested on Lantiq xRX200 (BT Home Hub 5A). Fixes: 9423361da523 ("net: lantiq: Disable IRQs only if NAPI gets scheduled ") Signed-off-by: Aleksander Jan Bajkowski Acked-by: Hauke Mehrtens Signed-off-by: David S. Miller --- drivers/net/ethernet/lantiq_xrx200.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c index 36dc3e5f6218..0e10d8aeffe1 100644 --- a/drivers/net/ethernet/lantiq_xrx200.c +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -352,8 +352,8 @@ static irqreturn_t xrx200_dma_irq(int irq, void *ptr) struct xrx200_chan *ch = ptr; if (napi_schedule_prep(&ch->napi)) { - __napi_schedule(&ch->napi); ltq_dma_disable_irq(&ch->dma); + __napi_schedule(&ch->napi); } ltq_dma_ack_irq(&ch->dma); -- cgit v1.2.3