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<DIV>To whom it may concern, </DIV>
<DIV> </DIV>
<DIV>we are using parts of the network driver from </DIV>
<DIV>the AV5282 BSP with our own BSP-Code. We have </DIV>
<DIV>enountered Problems when transmitting fragmented</DIV>
<DIV>IP Packets (i.e. send ICMP Ping with high amount </DIV>
<DIV>of dataload).</DIV>
<DIV> </DIV>
<DIV>We think that we might have found a bug in that </DIV>
<DIV>code in network.c so someone please could verify that. </DIV>
<DIV>(We still work on rtems-4.5.1 - nevertheless :-))</DIV>
<DIV> </DIV>
<DIV>If in the fec_sendpacket(..) an IP Fragment mbuffer </DIV>
<DIV>with zero length if(m->m_len) occurs then this packet</DIV>
<DIV>will be put on the mbuf chain, however. This will </DIV>
<DIV>result in used buffer descriptors that will never</DIV>
<DIV>be freed again. </DIV>
<DIV> </DIV>
<DIV>In our opinion/experience the following patch resolves </DIV>
<DIV>this problem: </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>*** network-orig.c Thu Jan 8 12:04:21 2009<BR>---
network.c Thu Jan 8 12:06:05 2009<BR>***************
fec_sendpacket(struct ifnet *ifp, struct<BR>*** 548,557 ****<BR>
* The IP fragmentation routine in ip_output<BR> *
can produce fragments with zero length.<BR> */<BR>-
txBd = sc->txBdBase + sc->txBdHead;<BR> if
(m->m_len){<BR> char *p = mtod(m, char *);<BR>
int offset = (int) p & 0x3;<BR> if
(offset == 0) {<BR> txBd->buffer = p;<BR>
txBd->length = m->m_len;<BR>--- 548,557
----<BR> * The IP fragmentation routine in ip_output<BR>
* can produce fragments with zero length.<BR>
*/<BR> if (m->m_len){<BR>
char *p = mtod(m, char *);<BR> int
offset = (int) p & 0x3;<BR>+ txBd = sc->txBdBase +
sc->txBdHead;<BR> if (offset == 0) {<BR>
txBd->buffer = p;<BR>
txBd->length = m->m_len;<BR></DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>Best regards, </DIV>
<DIV>Frank Ueberschar</DIV>
<DIV>---------------------------------------</DIV>
<DIV>DSA-Volgmann</DIV>
<DIV>Thomas Volgmann</DIV>
<DIV>Redcarstr. 20</DIV>
<DIV>53842 Troisdorf</DIV>
<DIV> </DIV>
<DIV>Tel: 02241 23416 16</DIV>
<DIV>Fax: 02241 23416 666</DIV>
<DIV>email : <FONT color=#0000ff><U>frank.ueberschar</U></FONT><A
href="mailto:frank.ueberschar@dsa-volgmann.de">@dsa-volgmann.de</A></DIV>
<DIV>web: <A
href="http://www.dsa-volgmann.de/">www.dsa-volgmann.de</A></DIV>
<DIV>---------------------------------------</DIV></DIV></BODY></HTML>