caif: Fix napi poll list corruption

herbertx · davem330 · commit 3079c652141f · 2014-12-22T16:34:39.000-05:00
The commit d75b1ad (net: less interrupt masking in NAPI) breaks caif. It is now required that if the entire budget is consumed when poll returns, the napi poll_list must remain empty. However, like some other drivers caif tries to do a last-ditch check and if there is more work it will call napi_schedule and then immediately process some of this new work. Should the entire budget be consumed while processing such new work then we will violate the new caller contract. This patch fixes this by not touching any work when we reschedule in caif. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/caif/caif_virtio.c b/drivers/net/caif/caif_virtio.c
@@ -257,7 +257,6 @@ static int cfv_rx_poll(struct napi_struct *napi, int quota)
 	struct vringh_kiov *riov = &cfv->ctx.riov;
 	unsigned int skb_len;
 
-again:
 	do {
 		skb = NULL;
 
@@ -322,7 +321,6 @@ static int cfv_rx_poll(struct napi_struct *napi, int quota)
 		    napi_schedule_prep(napi)) {
 			vringh_notify_disable_kern(cfv->vr_rx);
 			__napi_schedule(napi);
-			goto again;
 		}
 		break;
 
