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

Nicolas Ferre
2013-02-12T10:08:53Z

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@atmel.com>
---
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