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<p class="MsoNormal"><span style="font-size:11.0pt">I’m trying to get PPP working on SPARC/LEON3. I’m currently using RTEMS 4.11, but plan on switching to 5.x soon.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">While handshaking with a Linux PPP client, the LEON3 gets an unaligned memory trap in the GetMask function:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><a href="https://git.rtems.org/rtems/tree/cpukit/pppd/sys-rtems.c?h=4.11#n1299">https://git.rtems.org/rtems/tree/cpukit/pppd/sys-rtems.c?h=4.11#n1299</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">The second network interface returned by the ioctl(SIOGIFCONF) call is not aligned on a 4 byte boundary, so the pointer de-reference causes the trap.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">It looks like this was referenced in ticket 1401:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><a href="https://devel.rtems.org/ticket/1401">https://devel.rtems.org/ticket/1401</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:black;background:#FFFFDD">NOTE: the caller, when unpacking the</span><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:black"><br>
<span style="background:#FFFFDD">sequence of ifreqs is likely to encounter</span><br>
<span style="background:#FFFFDD">the same problem (see separate bug report</span><br>
<span style="background:#FFFFDD">filed for pppd)</span></span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I could not find that ticket for pppd. Did anyone try to create a fix for this?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Is the best approach to try to fix the pppd GetMask function to avoid unaligned accesses?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Thanks,<br>
Alan<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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