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<p class=MsoNormal>Hello,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I have been porting SCTP(Stream Control Transmission
Protocol) in RTEMS from FreeBSD. This is a transport layer protocol and resides
with TCP/UDP networking codes in kernel. I am mostly done with this port
and a number of SCTP socket API’s like socket, listen, bind,
accept, connect etc. works fine. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>However, I am now encountering some exception problems while
establishing SCTP connection between RTEMS SCTP endpoint with FreeBSD SCTP
endpoint via internet. The console shows:<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal style='margin-left:.5in'>Exception 6 caught at PC 191864 by
Thread 167831697<o:p></o:p></p>
<p class=MsoNormal style='margin-left:.5in'>Processor execution context at time
of the fault was:<o:p></o:p></p>
<p class=MsoNormal style='margin-left:.5in'>EAX 340012E7 EBX=384 ECX=FFFFFFFF
EX=0<o:p></o:p></p>
<p class=MsoNormal style='margin-left:.5in'>ESI=0 EDI=0 EBP=195838 ESP=195804<o:p></o:p></p>
<p class=MsoNormal style='margin-left:.5in'>Error code pushed by processor
itself (if not 0) = 0<o:p></o:p></p>
<p class=MsoNormal style='margin-left:.5in'>Faulty Thread will be deleted<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I tried to debug this problem by adding printf in codes but
was not able to detect the exact statement which causes this exception. Then I
have built RTEMS_GDB_Stub_1.4 (<a
href="http://www.slac.stanford.edu/~strauman/rtems/gdb/index.html">http://www.slac.stanford.edu/~strauman/rtems/gdb/index.html</a>)
for remote debugging and built my RTEMS SCTP application with
librtems-gdb-stub.a library. At this point, running the RTEMS application
crashes with:<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal style='margin-left:.5in'>GDB Agent: Exception (SIGILL)
caught; Task 0xA010001 Killed (Suspended) –use GDB<o:p></o:p></p>
<p class=MsoNormal style='text-indent:.5in'>Exception Vector #0x6; Registers:<o:p></o:p></p>
<p class=MsoNormal style='text-indent:.5in'>…………………<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>To investigate further with breakpoints, I have configured
gdb6.6 patched with RTEMS_GDB_Stub_1.4 in the host machine FC5. This works
fine and any break point in RTEMS application in <span style='font-family:"Courier New"'>init.c</span>
could be reachable by the host gdb. However, when I try to reach a breakpoint
in SCTP code which resides in <span style='font-family:"Courier New"'>cpukit/libnetworking/netinet</span>,
host gdb loses connection with the target machine and target application dies.<o:p></o:p></p>
<p class=MsoNormal> <o:p></o:p></p>
<p class=MsoNormal>In this point, I am not sure how should I proceed to solve
this problem. <o:p></o:p></p>
<p class=MsoNormal>I would appreciate any suggestion in this regard.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Best Regards,<o:p></o:p></p>
<p class=MsoNormal>Md Sazzadur Rahman<o:p></o:p></p>
<p class=MsoNormal>Graduate Student,<o:p></o:p></p>
<p class=MsoNormal>School of Computer Science,<o:p></o:p></p>
<p class=MsoNormal>University of Oklahoma, <o:p></o:p></p>
<p class=MsoNormal>Norman, Oklahoma, USA<o:p></o:p></p>
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