diff options
-rw-r--r-- | drivers/net/xen-netback/common.h | 5 | ||||
-rw-r--r-- | drivers/net/xen-netback/interface.c | 11 | ||||
-rw-r--r-- | drivers/net/xen-netback/netback.c | 16 |
3 files changed, 30 insertions, 2 deletions
diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h index 89b2d42..89d1d05 100644 --- a/drivers/net/xen-netback/common.h +++ b/drivers/net/xen-netback/common.h @@ -104,6 +104,11 @@ struct xenvif { domid_t domid; unsigned int handle; + /* Is this interface disabled? True when backend discovers + * frontend is rogue. + */ + bool disabled; + /* Use NAPI for guest TX */ struct napi_struct napi; /* When feature-split-event-channels = 0, tx_irq = rx_irq. */ diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index cdc298e..ef05c5c 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -63,6 +63,15 @@ static int xenvif_poll(struct napi_struct *napi, int budget) struct xenvif *vif = container_of(napi, struct xenvif, napi); int work_done; + /* This vif is rogue, we pretend we've there is nothing to do + * for this vif to deschedule it from NAPI. But this interface + * will be turned off in thread context later. + */ + if (unlikely(vif->disabled)) { + napi_complete(napi); + return 0; + } + work_done = xenvif_tx_action(vif, budget); if (work_done < budget) { @@ -363,6 +372,8 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, vif->ip_csum = 1; vif->dev = dev; + vif->disabled = false; + vif->credit_bytes = vif->remaining_credit = ~0UL; vif->credit_usec = 0UL; init_timer(&vif->credit_timeout); diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index ae34f5f..3f021e0 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -711,7 +711,8 @@ static void xenvif_tx_err(struct xenvif *vif, static void xenvif_fatal_tx_err(struct xenvif *vif) { netdev_err(vif->dev, "fatal error; disabling device\n"); - xenvif_carrier_off(vif); + vif->disabled = true; + xenvif_kick_thread(vif); } static int xenvif_count_requests(struct xenvif *vif, @@ -1212,7 +1213,7 @@ static unsigned xenvif_tx_build_gops(struct xenvif *vif, int budget) vif->tx.sring->req_prod, vif->tx.req_cons, XEN_NETIF_TX_RING_SIZE); xenvif_fatal_tx_err(vif); - continue; + break; } work_to_do = RING_HAS_UNCONSUMED_REQUESTS(&vif->tx); @@ -1808,7 +1809,18 @@ int xenvif_kthread_guest_rx(void *data) while (!kthread_should_stop()) { wait_event_interruptible(vif->wq, rx_work_todo(vif) || + vif->disabled || kthread_should_stop()); + + /* This frontend is found to be rogue, disable it in + * kthread context. Currently this is only set when + * netback finds out frontend sends malformed packet, + * but we cannot disable the interface in softirq + * context so we defer it here. + */ + if (unlikely(vif->disabled && netif_carrier_ok(vif->dev))) + xenvif_carrier_off(vif); + if (kthread_should_stop()) break; |