From dfd919285f2717e68788984352512d3fb5bee937 Mon Sep 17 00:00:00 2001 From: Harini Katakam Date: Tue, 7 May 2019 19:59:10 +0530 Subject: [PATCH] net: macb: Change interrupt and napi enable order in open [ Upstream commit 0504453139ef5a593c9587e1e851febee859c7d8 ] Current order in open: -> Enable interrupts (macb_init_hw) -> Enable NAPI -> Start PHY Sequence of RX handling: -> RX interrupt occurs -> Interrupt is cleared and interrupt bits disabled in handler -> NAPI is scheduled -> In NAPI, RX budget is processed and RX interrupts are re-enabled With the above, on QEMU or fixed link setups (where PHY state doesn't matter), there's a chance macb RX interrupt occurs before NAPI is enabled. This will result in NAPI being scheduled before it is enabled. Fix this macb open by changing the order. Fixes: ae1f2a56d273 ("net: macb: Added support for many RX queues") Signed-off-by: Harini Katakam Acked-by: Nicolas Ferre Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/cadence/macb_main.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index 7d7b513..74eeb3a 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -2419,12 +2419,12 @@ static int macb_open(struct net_device *dev) return err; } - bp->macbgem_ops.mog_init_rings(bp); - macb_init_hw(bp); - for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) napi_enable(&queue->napi); + bp->macbgem_ops.mog_init_rings(bp); + macb_init_hw(bp); + /* schedule a link state check */ phy_start(dev->phydev); -- 2.7.4