From 080d5c5ac8e4cfab4f3b1239667cf422925efcc3 Mon Sep 17 00:00:00 2001 From: Ivan Khoronzhuk Date: Mon, 22 Aug 2016 21:18:25 +0300 Subject: [PATCH] net: ethernet: ti: davinci_cpdma: fix locking while ctrl_stop The interrupts shouldn't be disabled while receiving skb, but while ctrl_stop, the channels are stopped and all remaining packets are handled with netif_receive_skb(), it can cause WARN_ONCE when ctrl is stopping while not all packets were handled with NAPIs: lock_irq_save cpdma_ctlr_stop cpdma_chan_top __cpdma_chan_free cpsw_rx_handler netif_receive_skb So, split locking while ctrl stop thus interrupts are still enabled while skbs handling. It can cause WARN_ONCE in rare cases when ctrl is stopping while not all packets were handled with NAPIs. Reviewed-by: Mugunthan V N Signed-off-by: Ivan Khoronzhuk Signed-off-by: David S. Miller --- drivers/net/ethernet/ti/davinci_cpdma.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/ethernet/ti/davinci_cpdma.c b/drivers/net/ethernet/ti/davinci_cpdma.c index 167fd659319d..ffb32af94f4c 100644 --- a/drivers/net/ethernet/ti/davinci_cpdma.c +++ b/drivers/net/ethernet/ti/davinci_cpdma.c @@ -334,12 +334,14 @@ int cpdma_ctlr_stop(struct cpdma_ctlr *ctlr) } ctlr->state = CPDMA_STATE_TEARDOWN; + spin_unlock_irqrestore(&ctlr->lock, flags); for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) { if (ctlr->channels[i]) cpdma_chan_stop(ctlr->channels[i]); } + spin_lock_irqsave(&ctlr->lock, flags); dma_reg_write(ctlr, CPDMA_RXINTMASKCLEAR, 0xffffffff); dma_reg_write(ctlr, CPDMA_TXINTMASKCLEAR, 0xffffffff); -- 2.20.1