[rtems-libbsd commit] if_ffec_mpc8xx: Fix incoming data invalidation

[Sebastian Huber]

Module:    rtems-libbsd
Branch:    master
Commit:    610349693dd31d8b0efd33776516b7187cc5cda2
Changeset: http://git.rtems.org/rtems-libbsd/commit/?id=610349693dd31d8b0efd33776516b7187cc5cda2

Author:    Sebastian Huber <sebastian.huber at embedded-brains.de>
Date:      Fri Sep 14 13:33:34 2018 +0200

if_ffec_mpc8xx: Fix incoming data invalidation

With a write-back cache dirty cache lines may be evicted which could
overwrite new data.

Close #3523.

---

 rtemsbsd/sys/dev/ffec/if_ffec_mpc8xx.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/rtemsbsd/sys/dev/ffec/if_ffec_mpc8xx.c b/rtemsbsd/sys/dev/ffec/if_ffec_mpc8xx.c
index a9d5eb4..bf20460 100644
--- a/rtemsbsd/sys/dev/ffec/if_ffec_mpc8xx.c
+++ b/rtemsbsd/sys/dev/ffec/if_ffec_mpc8xx.c
@@ -521,6 +521,7 @@ static void fec_rxDaemon (void *arg)
     rxBd = sc->rxBdBase + rxBdIndex;
     m = m_getcl(M_WAITOK, MT_DATA, M_PKTHDR);
     m->m_pkthdr.rcvif = ifp;
+    rtems_cache_invalidate_multiple_data_lines(mtod(m, void *), RBUF_SIZE);
     sc->rxMbuf[rxBdIndex] = m;
     rxBd->buffer = mtod (m, void *);
     rxBd->status = M8xx_BD_EMPTY;
@@ -578,19 +579,15 @@ static void fec_rxDaemon (void *arg)
       if (n != NULL) {
         /*
          * Pass the packet up the chain.
-         * FIXME: Packet filtering hook could be done here.
          */
-
-        /*
-         * Invalidate the buffer for this descriptor
-         */
-        rtems_cache_invalidate_multiple_data_lines(rxBd->buffer, rxBd->length);
-
         m = sc->rxMbuf[rxBdIndex];
         m->m_len = m->m_pkthdr.len = rxBd->length - ETHER_CRC_LEN;
         FEC_UNLOCK(sc);
         (*sc->ifp->if_input)(sc->ifp, m);
         FEC_LOCK(sc);
+
+        n->m_pkthdr.rcvif = ifp;
+        rtems_cache_invalidate_multiple_data_lines(mtod(n, void *), RBUF_SIZE);
       } else {
         /* Drop incoming frame if no new mbuf is available */
         n = m;
@@ -618,7 +615,6 @@ static void fec_rxDaemon (void *arg)
         sc->rxCollision++;
     }
 
-    n->m_pkthdr.rcvif = ifp;
     sc->rxMbuf[rxBdIndex] = n;
     rxBd->buffer = mtod (n, void *);