From 4dc78216f8ff86b572628e84aa24ad2f54da279f Mon Sep 17 00:00:00 2001 From: John Baldwin Date: Wed, 29 Apr 2015 17:48:25 +0000 Subject: [PATCH] Don't free mbufs when stopping an interface in netmap mode. Currently if you ifconfig down a vtnet interface while it is being used via netmap, the kernel panics due to trying to treat the cookie values in the virtio rings as mbufs to be freed. When netmap is enabled, these cookie values are pointers to something else. Note that other netmap-aware drivers don't seem to need this as they store the mbuf pointers in the software rings that mirror the hardware descriptor rings, and since netmap doesn't touch those, the software state always has NULL mbuf pointers causing the loops to free mbufs to not do anything. However, vtnet reuses the same state area for both netmap and non-netmap mode, so it needs to explicitly avoid looking at the rings and treating the cookie values as mbufs if netmap is enabled. Differential Revision: https://reviews.freebsd.org/D2348 Reviewed by: adrian, bryanv, luigi MFC after: 1 week Sponsored by: Norse Corp, Inc. --- sys/dev/virtio/network/if_vtnet.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/sys/dev/virtio/network/if_vtnet.c b/sys/dev/virtio/network/if_vtnet.c index 39fc28d41f45..704a3d95a54d 100644 --- a/sys/dev/virtio/network/if_vtnet.c +++ b/sys/dev/virtio/network/if_vtnet.c @@ -2745,6 +2745,11 @@ vtnet_drain_rxtx_queues(struct vtnet_softc *sc) struct vtnet_txq *txq; int i; +#ifdef DEV_NETMAP + if (nm_native_on(NA(sc->vtnet_ifp))) + return; +#endif /* DEV_NETMAP */ + for (i = 0; i < sc->vtnet_act_vq_pairs; i++) { rxq = &sc->vtnet_rxqs[i]; vtnet_rxq_free_mbufs(rxq);