From 0b545a62915aa635a5d41f64cbf3b7650c132a8d Mon Sep 17 00:00:00 2001 From: Sathya Perla Date: Fri, 23 Nov 2012 00:27:18 +0000 Subject: [PATCH] be2net: fix a possible events_get() race on BE2 On BE2 chip, an interrupt being raised even when EQ is in un-armed state has been observed a few times. This is not expected and has never been observed on BE3/Lancer chips. As a consequence, be_msix()::events_get() and be_poll()::events_get() can race and notify an EQ wrongly causing a CEV UE. The other possible side-effect would be traffic stalling because after notifying EQ, napi_schedule() is ignored as NAPI is already running. This patch fixes this issue by counting events only in be_poll(). Signed-off-by: Sathya Perla Signed-off-by: David S. Miller --- drivers/net/ethernet/emulex/benet/be_main.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c index c365722218ff..adef536c1586 100644 --- a/drivers/net/ethernet/emulex/benet/be_main.c +++ b/drivers/net/ethernet/emulex/benet/be_main.c @@ -2029,7 +2029,8 @@ static irqreturn_t be_msix(int irq, void *dev) { struct be_eq_obj *eqo = dev; - event_handle(eqo); + be_eq_notify(eqo->adapter, eqo->q.id, false, true, 0); + napi_schedule(&eqo->napi); return IRQ_HANDLED; } @@ -2125,9 +2126,11 @@ int be_poll(struct napi_struct *napi, int budget) { struct be_eq_obj *eqo = container_of(napi, struct be_eq_obj, napi); struct be_adapter *adapter = eqo->adapter; - int max_work = 0, work, i; + int max_work = 0, work, i, num_evts; bool tx_done; + num_evts = events_get(eqo); + /* Process all TXQs serviced by this EQ */ for (i = eqo->idx; i < adapter->num_tx_qs; i += adapter->num_evt_qs) { tx_done = be_process_tx(adapter, &adapter->tx_obj[i], @@ -2150,10 +2153,10 @@ int be_poll(struct napi_struct *napi, int budget) if (max_work < budget) { napi_complete(napi); - be_eq_notify(adapter, eqo->q.id, true, false, 0); + be_eq_notify(adapter, eqo->q.id, true, false, num_evts); } else { /* As we'll continue in polling mode, count and clear events */ - be_eq_notify(adapter, eqo->q.id, false, false, events_get(eqo)); + be_eq_notify(adapter, eqo->q.id, false, false, num_evts); } return max_work; } -- 2.20.1