[PATCH] net/macb: fix race with RX interrupt while doing NAPI

[Nicolas Ferre]

When interrupts are disabled, an RX condition can occur but
it is not reported when enabling interrupts again. We need to check
RSR and use napi_reschedule() if condition is met.

Signed-off-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
---
 drivers/net/ethernet/cadence/macb.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c
index a9b0830..b9d4bb9 100644
--- a/drivers/net/ethernet/cadence/macb.c
+++ b/drivers/net/ethernet/cadence/macb.c
@@ -693,6 +693,11 @@ static int macb_poll(struct napi_struct *napi, int budget)
 		 * get notified when new packets arrive.
 		 */
 		macb_writel(bp, IER, MACB_RX_INT_FLAGS);
+
+		/* Packets received while interrupts were disabled */
+		status = macb_readl(bp, RSR);
+		if (unlikely(status))
+			napi_reschedule(napi);
 	}
 
 	/* TODO: Handle errors */
-- 
1.8.0

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